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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?

User Lepanto
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1 Answer

5 votes

Answer:

Step-by-step 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)

User Ak
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