1. A researcher wants to assess the difficulty of test questions in an algebra class at a high school. To test it, he takes one question from each test given at the end of each week in the first semester. In statistical language, the individual questions taken from each of these weekly tests constitute a:

population

sample

population distribution

All of the above

2.The mean score on a creativity test is 70 and the standard deviation is 5. The distribution is considered to be normal. Using the percentage approximations for normal curves, how many people would get a score between 60 and 80?

34% + 34% = 68%

2% + 2% = 4%

14% + 34% + 34% + 14% = 96%

14%+34%=48%

3.Using the percentage approximations for normal distributions, what percentage of scores are between one standard deviation above the mean and two standard deviations above the mean?

16%

50%

14%

34%

4.A developmental psychologist conducts observations of 5 toddlers at a pre-school that has a total enrollment of 100 toddlers to examine rate of learning in general at the school. Which of the following is true?

The population in this example consists of all the toddlers in the school

The sample size includes all of the toddlers in the school

The population size and sample size are the same in this example

The population in this example consists of the 5 toddlers being observed

5. (FILL IN BLANK) Pretend you have a special deck of playing cards that contains a total of 98 individual cards. Each card is unique and only 1 cards have blue stars on them. If you shuffle the cards thoroughly and randomly draw one of them, what is the probability that the card will have a blue star on it? Round your answer to two decimal places. ____________________

6. (FILL IN BLANK) A person's raw score is 25.68, the mean is 31.18, and the standard deviation is 9.93. What is this person's Z score? Round your answer to two decimal places. ____________________________

7.The following question requires using a Z table. A community mental health center has found that on a 6-point scale about satisfaction with the services it provides to clients, the ratings are normally distributed with a mean of 3 and a standard deviation of .7. What percentage of clients rate their satisfaction above a 4?

92.36%

7.64%

0%

3.99%

8 ( FILL IN BLANK) .A Z score of -2.61 came from a distribution with a mean of 6.85 and a standard deviation of 4.75. What is the raw score? Round your answer to two decimal places. __________

9.The following question requires using a Z table. A person received a test score that is in the top 10% and the test scores follow a normal curve. This person's Z score must be at least:

1.28

1.04

2.03

1.58

10. ( FILL IN BLANK) In a housing community there are 96 households in which English is spoken, 58 in which Spanish is spoken, and 81 in which the language is other than English or Spanish. A researcher approaches a single house at random to conduct an interview. What is the probability that the language spoken in that household will not be English? Round your answer to two decimal places. ________

11.The following question requires using a Z table. On a normal curve, what percentage of scores are between a Z score of .95 and a Z score of 1.19?

0

5.41

10.29

4.88

12.The following question requires using a Z table. A person has a music aptitude score of 30, which equals a Z score of 1.45. What is the percentage of people above this score? (Assume a normal distribution.)

7.35%

5.00%

17.75%

92.65%

13,A statistics student wants to compare his final exam score to his friend's final exam score from last year; however, the two exams were scored on different scales. Suddenly, he remembers what he learned about the using Z scores to standardize raw scores for comparison purposes! He asks his friend for the mean and standard deviation of her class on the exam as well as her final exam score. He has the same information about his own exam. Here is the information:

Our student: Final exam score = 80; Class: M = 70 SD = 2

His friend: Final exam score = 85 Class: M = 60 SD = 5

In relation to the other people in their class, who had the better exam score?

His friend

They were equal

It is not possible to say without more information

Our statistics student

14.( FILL IN BLANK) At a particular small college, there are 252 students majoring in natural sciences, 335 in social sciences, 160 in humanities, and 66 in other majors. Suppose you select a student at random to interview about the college. What is the probability that this student would be someone majoring in either natural sciences or social sciences? Round your answer to two decimal places. __________

15.The following question requires using a Z table. What Z score would a person need to be in the top 15% of their class on a particular test? (Assume a normal distribution.)

Group of answer choices

-1.04

.39

1.04

0

-.39