1) Problem #PRAJ75F "PRAJ75F - 266047 - The mammals datas..." |
A mammals dataset contains data with average brain and body weights for 62 species of land mammals. The summary statistics for the brain weights in grams are found below: Given the summary statistics, one can conclude that this data set is: © STATS4STEM.ORG |
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2) Problem #PRAJGQB "PRAJGQB - 244498 - Which distributi..." |
Which distribution below represents the density curve above? © STATS4STEM.ORG |
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3) Problem #PRAKBZM "PRAKBZM - 269772 - Using the followi..." |
A)
Using the following dataset, please analyze the dataset under the assumption that the data represents exponential growth. Which of the above sets of graphs represent a transformation for exponential growth? © STATS4STEM.ORG |
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B)
After reviewing the graphical ouput, does the transformation provide a good linear fit? |
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C)
What is the equation of your line? |
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D)
Which equation best represents y-hat? A) y =10-0.0327+0.708x B) y-hat=10-0.0327+0.708*log(x) C) y-hat=10-0.0327+0.708x D) log(y-hat)=10-0.0327+0.708x E) log(y-hat)=10-0.0327+0.708*log(x) |
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E)
If x=0.9, calculated y-hat. Round answer to the nearest hundredth. |
4) Problem #PRAJBYM "PRAJBYM - 239950 - In what scenario ..." |
In what scenario can P(B|A)= P(B)? © STATS4STEM.ORG |
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5) Problem #PRAJBX7 "PRAJBX7 - 71-7-A" |
Discrete variables have countable outcomes. © STATS4STEM.ORG |
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6) Problem #PRAJBYU "PRAJBYU - 239957 - Agatha is a high ..." |
Agatha is a high school basketball player. The probability of her making a free throw is 65%. What is the probability that Agatha makes her first free throw on her fourth shot? Round answer to the nearest hundredths place. © STATS4STEM.ORG |
7) Problem #PRAE9HW "PRAE9HW - 148230 - The length of tim..." |
A)
The length of time it takes a person to play a certain video game is normally distributed with a mean of 20 minutes and standard deviation of 3 minutes. Find the probability it takes a random individual less than 16 minutes. Round answer to the nearest hundredth. Link to z-table. © STATS4STEM.ORG |
B)
Now, what is the probability that a sample of 2 individuals will have an average time less than 16 minutes. Round answer to the nearest hundredth. |
C)
Now, what is the probability that a sample of 10 individuals will have an average time greater than 21.4 minutes. Round answer to the nearest hundredth. |
D)
Now, what is the probability that a sample of 8 individuals will have an average time between 19 and 22 minutes. Answer as a decimal rounded to the nearest hundredth. |
8) Problem #PRAKESW "PRAKESW - 272447 - True or False, &n..." |
A)
True or False, Power is the probability of rejecting the null hypothesis when in fact it is false. © STATS4STEM.ORG |
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B)
Power = ? |
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C)
Which of the following cell or cells represent a Type I Error? Check all that apply.
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D)
Which of the previous cell or cells represent a Type II Error? Check all that apply. |
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E)
Which of the previous cell or cells represent a correct conclusion? Check all that apply. |
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9) 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 |
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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 |
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C)
What assumptions and conditions must be checked before proceeding with your test of significance? |
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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. |
E)
Using technology, determine the degrees of freedom for this problem? Round answer to the nearest hundredth. |
F)
Using techniology, calculate the p-value. Round answer to the nearest hundredth. |
G)
Which is the best conclusion to this problem. Assume the significance level is 0.05. |
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10) Problem #PRAJTCR "PRAJTCR - 253780 - The following for..." |
A)
The following formulas come from the AP formula sheet. Which of the following formulas can be used to help one remember/create the the confidence interval formula for a problem pertaining to the difference of proportions? © STATS4STEM.ORG |
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B)
Which of the formulas can be used to help one remember/create the test statistic needed for a hypothesis test for a problem pertaining to the difference of proportions? |
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11) Problem #PRAKMJQ "PRAKMJQ - 277990 - John, Amanda, and..." |
A)
John, Amanda, and Steve are best friends on Facebook. Each goes to a different school and they all take a final in US History. John scores a 95, Amanda scores a 72, and Steve scores a 42. John is interested in who did better. After a little research he finds the distributions for each respective school's US History final online. They are:
Based on the information found above, how would they rank, factoring in the fact that each school's score distribution is different? © STATS4STEM.ORG |
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B)
Another Facebook friend, Joey, joins their discussion. He goes to John's school, and he tells his friends that he scored 1.4 standard deviations above the mean. Based on this information, what is his z-score? |