Scores on a test have a mean of 70 and q3 is 83. the scores have a distribution that is approximately normal. find p90. (you will need to first find the standard deviation.)

a. 94.84

b. 85.08

c. 85.31

d. 83.7

Question

Mathematics

Angelina Barrett

12 October, 01:55

Scores on a test have a mean of 70 and q3 is 83. the scores have a distribution that is approximately normal. find p90. (you will need to first find the standard deviation.)

a. 94.84

b. 85.08

c. 85.31

d. 83.7

+4

Answers (1)

Know the Answer?

Shyla Baxter · Answer 1

Answer: Q3 represents 75%, meaning a z of ~0.67 80 - 70 is 10, so the standard deviations is ~14.9. 10 / 0.67 = 14.9 now find the z that represents a score of 90 90 - 70 is 20 20 / 14.9 = 1.34 from a z-table, a z of 1.34 represents a probability of ~90.99% meaning that there is about a 9.01% chance of getting a 90 or better.

Scores on a test have a mean of 70 and q3 is 83. the scores have a distribution that is approximately normal. find p90. (you will need to first find the standard deviation.)a. 94.84b. 85.08c. 85.31d. 83.7

Scores on a test have a mean of 70 and q3 is 83. the scores have a distribution that is approximately normal. find p90. (you will need to first find the standard deviation.)

a. 94.84

b. 85.08

c. 85.31

d. 83.7