7 MCQs in Statistics ...

Studies with humans typically   report that we remember an average of 7 out of 15 words given over an   80-minute retention interval. These studies also suggest a standard deviation   for the population of 2. Of the twenty subjects who received the drug during   the study, the average number of words remembered was 8.35. Using an alpha   level of 0.05, calculate the z-score.

2.99

3.07

3.02

3.42

The average score on the EKG test   is 89. The director of nursing examined 16 SICU registered nurses' scores.   They had an average score of 94 with a standard deviation of 8. At a level of   significance of 0.05, what should you conclude?

SICU nurses' scores are not     significantly different from the group.

SICU nurses' scores are significantly higher than the group.

SICU nurses' scores are     significantly lower than the group.

None of the above

Mrs. Benton's class had an average   of 85 on the TLI math test. The standard deviation for the class is 10.06. If   the girl's scores are 100, 65, 67, 72, 80, 85, 85, 73 and using a level of   significance of .05, what should we conclude?

The girl's average is not significantly different from the class.

The girl's average is     significantly different from the class.

Girls did significantly better     than the boys.

Boys did significantly better     than the girls.

A group of 16 students in the   teacher credentialing program are working together to study for a test. After   the test, they calculated their mean score to be 91%. The entire class mean   was 88% with a standard deviation of 4.43. Assuming you're working at 0.05   level of significance, what should you conclude?

The students' average is significantly better than the whole class.

The students' average is not     significantly better than the whole class.

We need the standard deviation     of the students' grades.

The z score is not the     appropriate test to use.

Mrs. Anderson's class has a mean   reading level of 38.4 with a standard deviation of 6.34. Mrs. Anderson wants   to compare the boy students' average reading level with the reading level of   the whole class. The boy students' reading levels are 28, 28, 34, 38, 38, 40,   40, 40, 50, 50. Using a significance level of .05, what is the z-score? a.   3.00

0.03

1.42

2.37

A third grade teacher wants to   compare her classes test scores to test scores nationwide. The population had   a mean of 82 with a standard deviation of 8. The sample size consisted of 20   students and the mean of their test scores is 76. Assuming you're working   with a significance level of 0.05, what should you conclude?

There is no significant     difference between the scores of the population and the sample.

The population scored significantly higher on the test.

The sample scored significantly     higher on the test.

There is not enough information     given.

Eight friends are in a study group   that meets weekly. After the last exam they compare the group's average score   (81.4) to the exam average and standard deviation, (78, 1.5), and realize   it's a small difference. Several of the group members want to quit because   they feel that the difference in test scores is insignificant. Using the .05   confidence level, what should you conclude?

There isn't enough information     to tell

There is no statistical     difference between the study group's scores and the population

There is a significant difference between the scores

The study group should not     continue to meet although it produces higher scores than the class