During 2001, 61.3% of US households purchased ground coffee.These households spent an average of $36.16 on ground coffee during the year. Consider the annual ground coffee expenditures for households purchasing ground coffee, assuming that these expenditures are approximately distributed as a normal random variable with a mean of $36.16 and a standard deviation of $10.00
a. Find the probability that the household spent less than $25.00
b. Find the probability that a household spent more than $50.00
c. Find the probability that a household spent more than $75.00
d. What proportion of the households spent between $30 and $40
e. 99% of the households spent less than what amount?
f. 80% of the households spent more than what amount?
g. Do you think that the assumption that the distribution of these expenditures is approximated by a normal distribution is valid. Explain.