What fraction of the terms in a normal distribution have z-scores between —2.41 and —.39

What fraction of the terms in a normal distribution have z-scores between —2.41 and —.39?

A. 2.02
B. .6437
C. .5129
D. 2.8
E. .3403

A new distribution is formed by taking the z-score of every term in a distribution whose mean is 6 with a standard deviation of .5. The mean and standard deviation of this new distribution is:
A. 6, .5
B. 1, 0
C. 6, .25
D. 0, .5
E. 0, 1



Consider a normal distribution that has N(55,7) (that is, a mean of 55 and a standard deviation of 7). To the nearest integer, the percentile rank of a value of 50 in this distribution is:

A. 76
B. 48
C. 43
D. 24
E. 71

1. Use a z table to get -2.41 = .008 and -.39 = .3483. Thus, .3483-.008 = .3473 or answer E

2. By using the z scores, the mean will be 0 with a SD of 1, or Answer E

3. (50 - 55) / 7 = -5/7 -.714. Using a z table, -.714 is .24, or Answer D