Question

The mean household income for a certain state is $69,000 with a standard deviation of $10,000. Assuming a normal distribution, about 95% of all households have an income over what amount?

A.$49,000
B.52,551
C.60,000
D.85,449
E.$89,000

Answer 1

$52,551

Explanation:

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Answer 2

B.52,551

Explanation:

Use a z-table to find the corresponding z-score.

P(z>Z) = 0.95

P(z<Z) = 0.05

z = -1.645

Now find the corresponding income:

z = (x − μ) / σ

-1.645 = (x − 69000) / 10000

x = 52550