Suppose x is a normal random variable with mean 60 and standard deviation 2.A z score was calculated for a number,and the z score is 3.4.What is x?
A)63.4
B)56.6
C)68.6
D)53.2
E)66.8

Question

Quizplus · Accepted Answer

We can use the formula for z-score:
z = (x - mean) / standard deviation

Plugging in the given values, we get:
3.4 = (x - 60) / 2

Multiplying both sides by 2, we get:
6.8 = x - 60

Adding 60 to both sides, we get:
x = 66.8

Therefore, the answer is E) 66.8.

Suppose X Is a Normal Random Variable with Mean 60