In a population of scores,X = 83 corresponds to z = -0.50 and X = 93 corresponds to z = +2.00.What are the values for the population mean and standard deviation?
A)µ = 85 and Ϭ = 4
B)µ = 85 and Ϭ = 2
C)µ = 81 and Ϭ = 4
D)µ = 81 and Ϭ = 6

Question

Quizplus · Accepted Answer

The z-score formula is z = (X - µ) / Ϭ. Using the two given points, we can set up two equations: (83 - µ) / Ϭ = -0.50 and (93 - µ) / Ϭ = 2. Solving these simultaneously gives µ = 85 and Ϭ = 4.

In a Population of Scores,X = 83 Corresponds to Z