Question

The mean household income for a certain state is $70,000 with a standard deviation of $10,000. Assuming a Normal distribution, about 95 percent of all households have an income over what amount?

Answer is 53,551 (How do I get this??)

Answer 1

$53,550

Explanation:

X ~ N(70,000 , 10,000²)

P(X > t) = 0.95

z = -1.645

-1.645 = (t - 70000)/10000

t - 70000 = -16450

t = 53,550