A national achievement test is administered annually to 3rd

A national achievement test is administered annually to 3rd graders. The test has a mean score of 100 and a standard deviation of 15. If Jane\'s z-score is 1.20, what was her score on the test?

Solution

he correct answer is (E). From the z-score equation, we know

z = (X - ?) / ?

where z is the z-score, X is the value of the element, ? is the mean of the population, and ? is the standard deviation.

Solving for Jane\'s test score (X), we get

X = ( z * ?) + 100 = ( 1.20 * 15) + 100 = 18 + 100 = 118