Question

During the past six months, 73.2% of US households purchased sugar. Assume that these expenditures are approximately normally distributed with a mean of $8.22 and a standard deviation of $1.10. 99% of the households spent less than what amount?

Answer 1

Answer:

Explanation:

Given X~Normal(mean=8.22, s=1.1)

So P(5<X<9) = P((5-8.22)/1.1 <(X-mean)/s < (9-8.22)/1.1)

=P(-2.93<Z< 0.71)

=0.7595 (check standard normal table)