1) Problem #PRAFJ9C "PRAFJ9C - Problem #157575" |
A)
A recent study of 28 high school students showed that the mean time it takes for them to complete a standardized math quiz is 9.3 minutes. The standard deviation of the sample was 2 minutes. Find the 90% confidence interval of the true mean. What is the lower limit of your confidence interval? Round answer to the nearest hundredth. Link to t-table © STATS4STEM.ORG |
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Lower Limit = 9.3-(1.703*(2/√28)) = 8.66 (ROUNDED) |
B)
What is the upper limit of your confidence interval? Round answer to the nearest hundredth. |
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Lower Limit = 9.3+(1.703*(2/√28)) = 9.94 (ROUNDED) |
2) Problem #PRAFJ9B "PRAFJ9B - 157574 - ILL - Confidence intervals - means - sigma not known" |
A)
The number of grams of carbohydrates in a 12-ounce serving of regular soft drink is listed here for a random sample of sodas. Estimate the mean number of carbohydrates in all brands of soda with 95% confidence. 48 37 52 40 43 46 41 38 41 45 45 33 35 52 45 41 30 34 46 40 What is the lower limit of your confidence interval? Answer as a decimal, and round answer to the nearest tenth. © STATS4STEM.ORG |
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x-bar is your sample mean Sx is your sample standard deviation n is your sample size |
B)
What is the upper limit of your confidence interval? Answer as a decimal, and round answer to the nearest tenth. |
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3) Problem #PRAFHH3 "PRAFHH3 - Once sample t confidence intervals - EJS" |
A)
A simple random sample (SRS) of the scores of 18 statistics students has a mean of 79. The standard deviation calculated from the sample is 6. We are going to calculate the 90% confidence interval of the mean scores of all statistics students. a) First, what is the number that represents the point estimate for this problem? © STATS4STEM.ORG |
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B)
What 2 conditions must be met before constructing a confidence interval for μ? Furthermore, explain how you know all conditions are met. |
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C)
Now, what is t* for a sample size of 18 and for a 90% confidence interval. Give answer exactly as listed on the t-table (don't round). Click here if you need a t-table. |
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D)
Now, calculate the margin of error for this problem. Round answer to the nearest hundredth. |
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E)
Now, lets go ahead and calculate the 90% confidence interval. The inteval can be broken into a lower limit and an upper limit. (Lower Limit, Upper Limit) What is the Lower Limit? Round answer to the nearest hundredth. |
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F)
What is the Upper Limit of a 90% confidence interval? Round answer to the nearest hundredth. |
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G)
A correct interpretation for the confidence interval would be: |
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4) Problem #PRAFHH2 "PRAFHH2 - t-star for CI" |
What is t* for a 90% Confidence Interval where the sample size is 39? Give answer exactly as found in the t-table. Click here for a t-table. © STATS4STEM.ORG |
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5) Problem #PRAFHHZ "PRAFHHZ - STATS4STEM.ORG" |
What is t* for a 80% Confidence Interval where the sample size is 57? *** Give answer EXACTLY as found in the t-table (three decimal places).*** Click here for a t-table. © STATS4STEM.ORG |
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6) Problem #PRAFHHY "PRAFHHY - STATS4STEM.ORG" |
What is t* for a 95% Confidence Interval where the sample size is 14? Give answer exactly as found in the t-table. Click here for a t-table. © STATS4STEM.ORG |
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7) Problem #PRAFGQQ "PRAFGQQ - Once sample t confidence intervals - EJS" |
A)
A simple random sample (SRS) of 19 books in the local library is collected. The sample has a mean book length of 281 pages. Assume the distribution for the population is normal, and standard deviation from the sample is 51 pages. We are going to calculate the 99% confidence interval of the mean number of pages for all books in the library. a) First, what is the number that represents the point estimate for this problem? © STATS4STEM.ORG |
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B)
What 3 conditions must be met before constructing a confidence interval for μ? Furthermore, explain how you know all conditions are met. |
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C)
Now, what is t* for a sample size of 19 and for a 99% confidence interval. Give answer exactly as listed on the t-table (don't round). Click here for a t-table. |
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D)
Now, calculate the margin of error for this problem. The margin of error is represented by the equation: Round answer to hundredths. |
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E)
Now, lets go ahead and calculate the 99% confidence interval. The inteval can be broken into a lower limit and an upper limit. (Lower Limit, Upper Limit) Where: Lower Limit = Point Estimate - margin of error Upper Limit = Point Estimate + margin of error What is the Lower Limit? Round answer to the nearest hundredths. |
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F)
Now, lets go ahead and calculate the 99% confidence interval. The inteval can be broken into a lower limit and an upper limit. (Lower Limit, Upper Limit) Where: Lower Limit = Point Estimate - margin of error Upper Limit = Point Estimate + margin of error What is the Upper Limit? Round answer to the nearest hundredths. |
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8) Problem #PRAJJ5G "PRAJJ5G - STATS4STEM.ORG" |
As the sample size increase, the t-distribution: © STATS4STEM.ORG |
Multiple Choice:
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9) Problem #PRAJKFX "PRAJKFX - STATS4STEM" |
A)
Review the different t-distribution density curves above. Are all t-distribution density curves centered at 0? © STATS4STEM.ORG |
Multiple Choice:
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B)
As the degrees of freedom increase, we can say that: |
Multiple Choice:
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C)
Is the following statement true or false? The only parameter that needs to be defined for the t-distribution is the degrees of freedom (df). This is unlike the Normal Distribution. The Normal Distribution requires two parameters to be defined: μ and σ . |
Multiple Choice:
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10) Problem #PRAJNC8 "PRAJNC8 - Calculate p value for t-dist" |
A)
Instructions on how use technology to calculate the p-value for the t-distribution. You will have to use either the TI-83 or R/Rweb to complete these Assistment questions as you will need to calculate the exact p-value. Knowing how to use the t-table will not be good enough to finish this Assistment. EXAMPLE #1 For df=8 and t=-2: TI-83 Instructions: To calculate the p-value using a TI-83, you would use the following procedure: Click 2nd -> DISTR -> tcd(-10, -2, 8) = 0.0403 ### tcd( LOWER #, HIGHER #, df) -> Use 10 and -10 for higher and lower limits R/Rweb Instructions: To calculate the p-value using R/Rweb, you would use the following function: pt(-2, 8) = 0.0403 ### P(X<t) = pt(t, df) Here is a shaded density curve that represents the above calculation: EXAMPLE #2 If df=18 and t=2.3: TI-83 Instructions: To calculate the p-value using a TI-83, you would use the following procedure: Click 2nd -> DISTR -> tcd(2.3, 10, 18) = 0.0168 ### tcd( LOWER #, HIGHER #, df) -> Use 10 and -10 for higher and lower limits R/Rweb Instructions: To calculate the p-value using R/Rweb, you would use the following function: P(X>2.3) = 1 - P(X<2.3) = 1-pt(2.3, 18) = 0.0168 ### P(X<t) = pt(t, df) Here is a shaded density curve that represents the above calculation: Calculate the p-value for a df=23, and t = -2.43. Round answer to the nearest hundredth. © STATS4STEM.ORG |
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To calculate the p-value using a TI-83, you would use the following procedure: Click 2nd -> DISTR -> tcd(-10, -2.43, 23) ### tcd( LOWER #, HIGHER #, df) -> Use 10 and -10 for higher and lower limits R/Rweb Instructions: To calculate the p-value using R/Rweb, you would use the following function: pt(-2.43, 23) ### P(X<t) = pt(t, df) |
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B)
Calculate the p-value for a df=18, and t=1.14. Round answer to the nearest hundredth. |
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To calculate the p-value using a TI-83, you would use the following procedure: Click 2nd -> DISTR -> tcd(1.14, 10, 18) ### tcd( LOWER #, HIGHER #, df) -> Use 10 and -10 for higher and lower limits R/Rweb Instructions: To calculate the p-value using R/Rweb, you would use the following function: P(X>1.14) = 1 - P(X<1.14) = 1-pt(1.14, 18) ### P(X<t) = pt(t, df) |
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C)
Calculate the p-value for a df=27, and t=0.64. Round answer to the nearest hundredth.
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To calculate the p-value using a TI-83, you would use the following procedure: Click 2nd -> DISTR -> tcd(0.64, 10, 27) ### tcd( LOWER #, HIGHER #, df) -> Use 10 and -10 for higher and lower limits R/Rweb Instructions: To calculate the p-value using R/Rweb, you would use the following function: P(X>0.64) = 1 - P(X<0.64) = 1-pt(0.64, 27) ### P(X<t) = pt(t, df) |
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D)
Calculate the p-value for a df=14, and t = -1.28. Round answer to the nearest hundredth. |
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To calculate the p-value using a TI-83, you would use the following procedure: Click 2nd -> DISTR -> tcd(-10, -1.28, 14) ### tcd( LOWER #, HIGHER #, df) -> Use 10 and -10 for higher and lower limits R/Rweb Instructions: To calculate the p-value using R/Rweb, you would use the following function: pt(-1.28, 14) ### P(X<t) = pt(t, df) |
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11) Problem #PRAJNDE "PRAJNDE - STATS4STEM.ORG" |
A)
McGonalds Burger advertises a quarter pound (0.25 lb) cheesburger. A local burger lover feels that the burgers actually have less meat than advertised. To prove his claim, he randomly purchases 12 burgers and measures and records the weight in pounds. The data is below:0.19 0.23 0.30 0.22 0.24 0.23 0.23 0.22 0.29 0.21 0.23 0.23 What is the best formula to calculate the test statistic for this problem? A. B. C. D. © STATS4STEM.ORG |
Multiple Choice:
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B)
What assumptions and condition must be checked before proceeding with your test of significance? |
Check All That Apply:
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C)
Calculate the test statistic, t, for this problem. Round answer to the nearest hundredths. |
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Also, make sure to calculate t using an x-bar and s rounded to at least the thousands place. If you round x-bar and s to the hundredths place, your t value may be off by too much. For example : x-bar = 3.215 (GOOD) x-bar = 3.22 (BAD) |
s = 0.031 μ0 = 0.25 n = 12 |
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D)
Using either the TI-83 or R/Rweb, calculate the p-value. Round answer to the nearest hundredth. |
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To calculate the p-value using a TI-83, you would use the following procedure: Click 2nd -> DISTR -> tcd(-10, -1.68, 11) ### tcd( LOWER #, HIGHER #, df) -> Use 10 and -10 for higher and lower limits R/Rweb Instructions: To calculate the p-value using R/Rweb, you would use the following function: pt(-1.68, 11) ### P(X<t) = pt(t, df) |
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E)
State the conclusion in the context of the problem. |
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F)
For this problem, calculate the margin of error for a 95% confidence interval. Round answer to the nearest hundredth. |
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12) Problem #PRAJNDM "PRAJNDM - STATS4STEM.ORG" |
A)
Twenty-one elastic bands were randomly divided into two groups. One of the sets was placed in hot water (60-65 degrees C) for four minutes, while the other was left at ambient temperature. After a wait of about ten minutes, the amounts of stretch, under a 1.35 kg weight, were recorded. A researcher wishes to prove that heated bands stretch more than bands stretched while at ambient temperature.What is the best formula to calculate the test statistic for this problem? A. B. C. D. E. © STATS4STEM.ORG |
Multiple Choice:
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B)
Which of the following represent the correct null and alternative hypothesis? Notation: H - Heated; A - Ambient A) H0: μH = 0 Ha: μH < μA B) H0: μH = μA Ha: μH < μA C) H0: μH = 0 Ha: μH ≠ μA D) H0: μH = μA Ha: μH > μA E) H0: μH ≠ μA Ha: μH > μA F) H0: μH = 0 Ha: μH > μA G) None of the above |
Multiple Choice:
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C)
What assumptions and condition must be checked before proceeding with your test of significance? |
Check All That Apply:
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D)
Calculate the test statistic, t, for this problem. Round answer to the nearest hundredths. |
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Also, make sure to calculate t using an x-bar and s rounded to at least the thousands place. If you round x-bar and s to the hundredths place, your t value may be off by too much. ROUNDING EXAMPLE : x-bar = 3.215 (GOOD) x-bar = 3.22 (BAD) |
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E)
What is the degrees of freedom for this problem? If using technology, round answer to the nearest hundredth. |
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If using technology, df = 18.9158 or 18. 92 (More accurate) *** Both answers are acceptable, based on which method you choose to use. |
F)
Using either the TI-83 or R/Rweb, calculate the p-value. Round answer to the nearest hundredth. |
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To calculate the p-value using a TI-83, you would use the following procedure: Click 2nd -> DISTR -> tcd(1.99, 10, 9) ### tcd( LOWER #, HIGHER #, df) -> Use 10 and -10 for higher and lower limits R/Rweb Instructions: To calculate the p-value using R/Rweb, you would use the following function: 1 - pt(1.99, 9) ### P(X<t) = pt(t, df) |
p-value = 0.04 (Conservative Estimate) If using technology, df = 18.9158 p-value = 0.03 (More accurate) |
G)
Please state your conclusion for this hypothesis test in the context of the problem. |
Ungraded Open Response: |
H)
For this problem, calculate the margin of error for a 99% confidence interval. Round answer to the nearest hundredth. |
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margin of error = 15.37 (Conservative Estimate) If using technology, df = 18.9158 margin of error = 13.54 (More accurate) *** Both answers are acceptable depending on approach. |
13) Problem #PRAJNKC "PRAJNKC - STATS4STEM.ORG" |
A)
To carry out a hypothesis test using a TI-83 for the difference of two independent population means: If the two datasets for the problem are given: 1) First enter the datasets into them into lists, say L1 and L2. 2) Press "STAT", scroll right to "TESTS", press 4 for 2-SampTTest, and select "Inpt:DATA". 3) Enter the location of the lists, and the frequencies (1). Choose the type of alternative (one-sided or two sided). 4) Select whether you want pooled standard deviations or not (recommendation: NO). Scroll to "Calculate" and press ENTER. 5) You can see the t-score, the p-value, an approximated value for the degrees of freedom, the sample means, and the sample standard deviations. If the statistics for the problem are given: 1) Press "STAT", scroll right to "TESTS", press 4 for 2-SampTTest, and select "Inpt:Stats". 2) Enter the sample standard deviation Sx, the sample mean, and the sample size for both samples. 3) Choose the type of alternative (one-sided or two sided) and decide whether you want pooled standard deviations or not.. Scroll down to "Calculate" and press ENTER. 4) Select whether you want pooled standard deviations or not (recommendation: NO). Scroll to "Calculate" and press ENTER. 5) You can see the t-score, the p-value, and an approximated value for the degrees of freedom. ---------------- Data was collected to reinforce the claim that μA < μB
Using the statistics found above and your TI-83, calculate the test statistic, t, for this problem. Round answer to the nearest hundredth. © STATS4STEM.ORG |
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1) Press "STAT", scroll right to "TESTS", press 4 for 2-SampTTest, and select "Inpt:Stats". 2) Enter the sample standard deviation Sx, the sample mean, and the sample size for both samples. 3) Choose the type of alternative (one-sided or two sided) and decide whether you want pooled standard deviations or not.. Scroll down to "Calculate" and press ENTER. 4) You can see the t-score, the p-value, and an approximated value for the degrees of freedom. |
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B)
What is your p-value? Round answer to the nearest hundredth. |
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C)
What is the degrees of freedom? Round answer to the nearest hundredth. |
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14) Problem #PRAJNPH "PRAJNPH - 249278 - A speed reading c..." |
A)
A speed reading company claims that their product reduces the time it takes to read a page. To prove their claim, 12 random individuals were timed on their ability to read a page. This data was recorded as sample A. The individuals then took a two-day speed reading class offered by the company and were timed again after taking the class. Their second recorded time was recorded as sample B. To prove their claim, which of the following test statistics should be used? A. B. C. D. E. © STATS4STEM.ORG |
Multiple Choice:
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B)
Calculate the test statistic, t. Round answer to the nearest hundredth. |
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s = 4.843 μ0 = 0 |
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C)
Calculate the p-value for this hypothesis test. Round answer to the nearest hundredth. |
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To calculate the p-value using a TI-83, you would use the following procedure: Click 2nd -> DISTR -> tcd(-10, -1.43, 11) ### tcd( LOWER #, HIGHER #, df) -> Use 10 and -10 for higher and lower limits R/Rweb Instructions: To calculate the p-value using R/Rweb, you would use the following function: pt(-1.43, 11) ### P(X<t) = pt(t, df) |
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D)
Calculate the margin of error for a 99% confidence interval. Round answer to the nearest hundredth. |
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15) Problem #PRAJQ5U "PRAJQ5U - 251644 - 18 random history..." |
A)
18 random history students correctly answer 79 questions on a national history exam. The standard deviation of the sample is 6. We must calculate a 90% confidence interval of the mean number of scores answered by correctly by all students taking the exam in the nation. What number represents the point estimate for this confidence interval? © STATS4STEM.ORG |
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B)
What is t* for a sample size of 18? Use exact t* found using t-table. Don't round. Link to t-table |
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C)
Calculate the margin of error for this problem. Round answer to the nearest hundreth. |
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D)
Find the Lower Limit of the Interval. Round to the nearest hundreth. |
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E)
Find the Upper Limit of the Interval. Round to the nearest hundreth. |
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16) Problem #PRAJSD7 "PRAJSD7 - 252864 - Assign monday 2.5" |
A)
This problem uses the seeds dataset. Scientists often research relationships between seed types and the number of germinated seeds. For this problem, researchers wish to show that seed type 1 creates more germinated seeds than seed type 0. The data below shows data from a randomized experiment. The data displays the number of germinated seeds by seed type for the experiment. What is the best formula to calculate the test statistic for this problem? A. B. C. D. E. © STATS4STEM.ORG |
Multiple Choice:
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B)
Which of the following represent the correct null and alternative hypothesis? Notation: 0 - Seed Type 0; 1 - Seed Type 1 A) H0: μ1 = 0 Ha: μ1 > μ0 B) H0: x-bar1 = x-bar0 Ha: x-bar1 > x-bar0 C) H0: μ1 = μ0 Ha: μ1 > μ0 D) H0: μ1 = μ0 Ha: μ1 < μ0 E) H0: p1 ≠ p0 Ha: p1 > p0 F) H0: x-bar1 = 0 Ha: x-bar1 > x-bar0 G) None of the above |
Multiple Choice:
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C)
What assumptions and condition must be checked before proceeding with your test of significance? |
Check All That Apply:
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D)
While taking the AP Statistics exam, it is suggested that one: |
Check All That Apply:
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E)
For the remainder of the problems for this assistment, YOU MUST use technology to calculate t, df, and the p-value for this problem. Specifically, one must use the two sample t-test feature of the TI-83 to obtain the remaining answers. This assistment does not support answers derived from using the t-table. Using technology, calculate the test statistic, t, for this problem. Round answer to the nearest hundredths. |
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F)
Using technology, dermine the degrees of freedom for this problem? Round answer to the nearest hundredth. |
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G)
Using either the TI-83 or R/Rweb, calculate the p-value. Round answer to the nearest hundredth. *** You must use technology for this problem to get the correct answer. The t-table will not provide an accurate enough answer. |
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H)
State your conclusion for this problem: |
Ungraded Open Response: |
17) Problem #PRAJTSB "PRAJTSB - Excercise company statistics" |
A)
An exercise company has created a new exercise machine that they feel will be an improvement to their existing machine currently being sold in the market. The CEO of the company designed and built the existing machine and he is skeptical that the new machine is better and he asks for proof. The company places an ad in the local paper asking for volunteers for a weight training study. 32 people respond and are randomly assigned to two groups. Group 1 uses the new exercise equipment, while group 2 uses the old exercise equipment. The following data represents the improvement in strength (in pounds) over a 4 week period. Can the company claim that the new equipment is an improvement over the old equipment? What is the best formula to calculate the test statistic for this problem? A. B. C. D. E. © STATS4STEM.ORG |
Multiple Choice:
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B)
Which of the following represent the correct null and alternative hypothesis? Notation: 1 - Group 1; 2 - Group 2 A) H0: μ1 = 0 Ha: μ1 > μ2 B) H0: μ1 = μ2 Ha: μ1 < μ2 C) H0: μ1 = μ2 Ha: μ1 > μ2 D) H0: μ1 = 0 Ha: μ1 ≠ μ2 E) H0: μ1 ≠ μ2 Ha: μ1 > μ2 F) H0: μ1 = 0 Ha: μ1 > μ2 G) None of the above |
Multiple Choice:
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C)
What assumptions and conditions must be checked before proceeding with your test of significance? |
Check All That Apply:
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D)
For the remainder of the problems, one must use either the TI-83 or Rweb to calculate t, the degrees of freedom, and the p-value. Use of just the t-table will not be provide answers that are sufficiently accurate enough for ASSISTments. Using technology, calculate the test statistic, t, for this problem. Round answer to the nearest hundredths. |
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First enter your data into the list editor. Then, click: 1) STAT 2) Scroll to TESTS 3) Sroll down to 2-SampleTTest 4) Inpt: Data |
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E)
Using technology, determine the degrees of freedom for this problem? Round answer to the nearest hundredth. |
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F)
Using techniology, calculate the p-value. Round answer to the nearest hundredth. |
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G)
Which is the best conclusion to this problem. Assume the significance level is 0.05. |
Multiple Choice:
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18) Problem #PRAJT5P "PRAJT5P - 254522 - Harry Potter deci..." |
A)
Harry Potter decides to use his fame to start a coffee business called Magical Coffee. His first brand of coffee was called Magic Potion #9. But sales were slow, so he decided to brew up a new type of coffee. He decided to call his new brand of coffee Siriously Black. However, he wasn't sure if his new coffee was actually better than his old coffee. So, he decided to run a blind taste test by choosing 12 coffee drinkers to try the two types of coffee and rate both coffees on a scale of 1-10. To randomize the experiment, half the drinkers were asked to drink Magic Potion #9 first, followed by Siriously Black. The other half were asked to drink Siriously Black first, followed by Magic Potion #9. Based on the data below, can Harry claim that his new Siriously Black coffee is better than his old Magic Potion #9 coffee? To prove their claim, which of the following formulas should be used to calculate the test statistic? A. B. C. D. E. © STATS4STEM.ORG |
Multiple Choice:
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B)
Which of the following represent the correct null and alternative hypothesis? A) H0: μdiff = 0 Ha: μdiff > 0 B) H0: μSB = μMP Ha: μSB < μMP C) H0: μdiff < 0 Ha: μdiff > 0 D) H0: μSB < 0 Ha: μSB ≠ μMP E) H0: μSB = μMP Ha: μSB > μMP F) H0: μdiff = 0 Ha: μdiff ≠ 0 |
Multiple Choice:
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C)
For this problem, calculate the following statistic: Round answer to the nearest hundredth. |
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D)
Calculate the test statistic, t. Round answer to the nearest hundredth. |
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s = 1.138 μ0 = 0 n=12 |
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E)
What is the degrees of freedom for this problem? |
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F)
Using the TI-83 or Rweb, calculate the p-value for this hypothesis test. Round answer to the nearest hundredth. *** You must use technology for this problem to get the correct answer. The t-table will not provide an accurate enough answer. |
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G)
Which of the following is the best conclusion to this problem? |
Multiple Choice:
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19) Problem #PRAJT8D "PRAJT8D - Harry - Coffee - CI" |
A)
Harry Potter decides to use his fame to start a coffee business called Magical Coffee. His first brand of coffee was called Magic Potion #9. But sales were slow, so he decided to brew up a new type of coffee. He decided to call his new brand of coffee Siriously Black. However, he wasn't sure if his new coffee was actually better than his old coffee. So, he decided to run a blind taste test by choosing 12 coffee drinkers to try the two types of coffee and rate both coffees on a scale of 1-10. To randomize the experiment, half the drinkers were asked to drink Magic Potion #9 first, followed by Siriously Black. The other half were asked to drink Siriously Black first, followed by Magic Potion #9. Based on the data below, calculate a 90% confidence interval to estimate the mean impovement in the Siriously Black coffee over the Magic Potion. Which of the following formulas should be used to calculate the confidence interval? A. B. C. D. E. © STATS4STEM.ORG |
Multiple Choice:
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B)
Calculate the lower number of the interval. Round answer to the nearest hundredth. Link to t-table. |
Algebraic Expression:
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Hints: |
x-bardiff = 0.25 sdiff = 1.1382 n = 12 |
Answer = -0.34 |
C)
Calculate the upper number of the interval. Round answer to the nearest hundredth.
|
Algebraic Expression:
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Hints: |
x-bardiff = 0.25 sdiff = 1.1382 n = 12 |
Answer = 0.84 |
20) Problem #PRAJVG9 "PRAJVG9 - 255842 - A bottling compan..." |
A)
A bottling company claims to fill up their bottles with 12 oz. A local consumer groups feels that the company fills their bottles with less than that. To prove their claim, they randomly sample 14 bottles. The data is found below. Does the data support their claim? Which of the following is the most appropriate formula for calculating the test statistic for this problem? A) B) C) D) E) © STATS4STEM.ORG |
Multiple Choice:
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B)
Which of the following null and alternative hypothesis is most appropriate for this test? A) H0: x-bar > 12 Ha: x-bar < 12 B) H0: μ = 12 Ha: μ > 12 C) H0: μ = 12 Ha: μ ≠ 12 D) H0: μ = 12 Ha: μ < 12 E) H0: x-bar ≠ 12 Ha: x-bar < 12 F) H0: x-bar = 12 Ha: x-bar < 12 G) H0: μ > 12 Ha: μ < 12 |
Multiple Choice:
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C)
Using a TI-83 or Rweb, calculate the sample mean. Round answer to the nearest hundredth. |
Algebraic Expression:
|
Hints: |
Use List Editor - Enter data into L1 - Then Use STAT->CALC->1-VAR STATS L1 Example Code Using Rweb: x=c(1,2,3) ### Enter data into variable x mean(x) ### Calculate the mean of x |
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D)
Calculate the test statistic, t, for this problem. Round answer to the nearest hundredth. |
Algebraic Expression:
|
Hints: |
|
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E)
What is the degrees of freedom? |
Algebraic Expression:
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Hints: |
Therefore, df = 14 - 1 = 13 |
F)
Using either the TI-83 or R/Rweb, calculate the p-value. Round answer to the nearest hundredth. Click here for help to use either the TI-83 or R/Rweb to calculate probabilites for the t distribution. *** You must use technology for this problem to get the correct answer. The t-table will not provide an accurate enough answer. |
Algebraic Expression:
|
Hints: |
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G)
Write conclusion. Make sure to state conculsion using the context of the problem. |
Ungraded Open Response: |
H)
For this problem, what condition(s) need to be checked? Are the condition(s) satisfied? How do you know? |
Ungraded Open Response: |
21) Problem #PRAJ8HT "PRAJ8HT - 266430 - Fruit by the Foot..." |
A)
Fruit by the Foot claims that it is 3 feet of delicious fun. However, a consumer group believes that it's actually less than 3 feet. So they randomly sample 10 pieces of candy and measure the lengths in feet. The data is as follows: 3.1, 3.3, 2.9, 2.7, 2.8, 2.8, 2.6, 3.0, 2.8, 3.1 Does the data support the claim that the length is actually less than 3 feet? Which of the following is the most appropriate formula for calculating the test statistic for this problem? A) B) C) D) E) F) © STATS4STEM.ORG |
Multiple Choice:
|
B)
Which of the following null and alternative hypothesis is most appropriate for this test? A) H0: x-bar > 3 Ha: x-bar < 3 B) H0: μ = 3 Ha: μ > 3 C) H0: μ = 3 Ha: μ ≠ 3 D) H0: μ = 3 Ha: μ < 3 E) H0: x-bar ≠ 3 Ha: x-bar < 3 F) H0: x-bar = 3 Ha: x-bar < 3 G) H0: μ > 3 Ha: μ < 3 |
Multiple Choice:
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C)
Using a TI-83 or Rweb, calculate the sample mean. Round answer to the nearest hundredth. |
Algebraic Expression:
|
Hints: |
Use List Editor - Enter data into L1 - Then Use STAT->CALC->1-VAR STATS L1 s = Sx Example Code Using Rweb: x=c(1,2,3) ### Enter data into variable x mean(x) ### Calculate the mean of x |
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D)
Calculate the test statistic, t, for this problem. Round answer to the nearest hundredth. |
Algebraic Expression:
|
Hints: |
|
|
E)
What is the degrees of freedom? |
Algebraic Expression:
|
Hints: |
Therefore, df = 10 - 1 = 9 |
F)
Using either the TI-83 or R/Rweb, calculate the p-value. Round answer to the nearest hundredth. Click here for help to use either the TI-83 or R/Rweb to calculate probabilites for the t distribution. *** You must use technology for this problem to get the correct answer. The t-table will not provide an accurate enough answer. |
Algebraic Expression:
|
Hints: |
|
G)
Write conclusion. Make sure to state conculsion using the context of the problem. |
Ungraded Open Response: |
H)
For this problem, what condition(s) need to be checked? Are the condition(s) satisfied? How do you know? |
Ungraded Open Response: |
22) Problem #PRAKEHR "PRAKEHR - 272194 - A potato chip com..." |
A)
A potato chip company claims to fill up their bags of chips with 10 oz. A local consumer group feels that the company fills their bags with less than that. To prove their claim, they randomly sample 14 bags. The data is found below. Does the data support their claim? 9.3 10.4 10.0 8.9 9.8 9.5 11.0 10.6 9.9 10.2 8.4 9.4 9.0 10.1 Which of the following is the most appropriate formula for calculating the test statistic for this problem? A) B) C) D) E) © STATS4STEM.ORG |
Multiple Choice:
|
B)
Which of the following null and alternative hypothesis is most appropriate for this test? A) H0: x-bar > 10 Ha: x-bar < 10 B) H0: μ = 10 Ha: μ > 10 C) H0: μ = 10 Ha: μ ≠ 10 D) H0: μ = 10 Ha: μ < 10 E) H0: x-bar ≠ 10 Ha: x-bar < 10 F) H0: x-bar = 10 Ha: x-bar < 10 G) H0: μ > 10 Ha: μ < 10 |
Multiple Choice:
|
C)
For this problem, what condition(s) need to be checked? Are the condition(s) satisfied? How do you know? |
Ungraded Open Response: |
D)
Using a TI-83 or Rweb, calculate the sample mean. Round answer to the nearest hundredth. |
Algebraic Expression:
|
Hints: |
Use List Editor - Enter data into L1 - Then Use STAT->CALC->1-VAR STATS L1 Example Code Using Rweb: x=c(1,2,3) ### Enter data into variable x mean(x) ### Calculate the mean of x |
|
E)
Calculate the test statistic, t, for this problem. Round answer to the nearest hundredth. |
Algebraic Expression:
|
Hints: |
|
|
F)
What is the degrees of freedom? |
Algebraic Expression:
|
Hints: |
Therefore, df = 14 - 1 = 13 |
G)
Using either the TI-83 or R/Rweb, calculate the p-value. Round answer to the nearest hundredth. Click here for help to use either the TI-83 or R/Rweb to calculate probabilites for the t distribution. *** You must use technology for this problem to get the correct answer. The t-table will not provide an accurate enough answer. |
Algebraic Expression:
|
Hints: |
|
H)
Write conclusion. Make sure to state conculsion using the context of the problem. |
Ungraded Open Response: |