a score of 66 on a test with a mean of 72 and a standard deviation of 8.3 find the score of the test.

Question

a score of 66 on a test with a mean of 72 and a standard deviation of 8.3 find the score of the test.

Answer 1

(raw score minus mean)/standard deviatuion =

(66-72)/8.3

= z score

= about -.7289

using a z score calculator or z tables

Pr(x<66)= about 23.303% scored less than 66

76.697% scored better than 66

66 is in the 23rd percentle

and in the 1st quartile, Q1, bottom 4th of the class