Chapter 2 Test

Test scores for a certain college placement test are approximately normally distributed with mean 34 and standard deviation 5. What is the range of scores for the middle 95% of the distribution?

(A) 29 to 39

(B) 19 to 44

(C) 19 to 49

(D) 24 to 44

(E) 29 to 44

• A

• B

• C

• D

• E

The mean and standard deviation of a set of data are 29 and 4.23 respectively. If each data value is multiplied by 3 and then 5 is added to each value, the resulting mean and standard deviation will be

(A) 29 and 4.23

(B) 29 and 12.69

(C) 92 and 4.23

(D) 92 and 12.69

(E) 2 and 17.69

• A

• B

• C

• D

• E

The box plots below summarize two data sets, A and B. Which of the following must be true?

I. Set A contains more data than Set B.

II. Set A and Set B have different means.

III. Set A data have a larger range than Set B data.

A) I only

B) III only

C) I and II only

D) II and III only

E) I, II, and III

• A

• B

• C

• D

• E

A company sampled the medical expenses from the prior year for 25 employees. Later the company discovered that the highest medical expense in the sample was mistakenly recorded as 10 times the actual amount. However, after correcting the error, the corrected amount was still greater than or equal to any other medical expense in the sample. Which of the following sample statistics must have remained the same after the correction was made?

A) Mean

B) Median

C) Mode

D) Range

E) Variance

• A

• B

• C

• D

• E

At a college the scores on the chemistry final exam are approximately normally distributed, with a mean of 75 and a standard deviation of 12. The scores on the calculus final are also approximately normally distributed, with a mean of 80 and a standard deviation of 8. A student scored 81 on the chemistry final and 84 on the calculus final. Relative to the students in each respective class, in which subject did this student do better?

A) The student did better in chemistry.

B) The student did better in calculus.

C) The student did equally well in each course.

D) There is no basis for comparison, since the subjects are different from each other and are in different departments.

E) There is not enough information for comparison, because the number of students in each class is not known.

• A

• B

• C

• D

• E

The figure below shows a CUMULATIVE relative frequency histogram of 40 scores on a test given in an AP Statistics class. Which of the following conclusions can be made from the graph?

A) There is greater variability in the lower 20 test scores than in the higher 20 test scores.

B) The median test score is less than 50.

C) Sixty per cent of the students had test scores above 80.

D) If the passing score is 70, most students did not pass the test.

E) The horizontal nature of the graph for test scores of 60 and below indicates that those scores occurred most frequently.

• A

• B

• C

• D

• E

What is the formula to find the z-score for population?

• z=X-M

• z=σ-M/μ

• ^z/M=μ

• z=X-μ/σ

Tags

CCSS.HSS.ID.A.4

The sign of the z-score indicates whether the location is above(positive) or below(negative) the mean.

• True

• False

Tags

CCSS.HSS.ID.A.4

Find the z-score value corresponding if the location is below the mean by 2 standard deviations

• +2.00

• -2.00

• +1.25

• -1.00

Tags

CCSS.HSS.ID.A.4

The average waist size for teenage males is 29 inches with a standard deviation of 2 inches. 
If waist sizes are normally distributed, determine the z-score of a teenage male with a 33 inch waist.  

• 2
• 1
• -2
• -1

Tags

CCSS.HSS.ID.A.4