At a local supermarket the amount spent by a shopper during a single trip follows a normal distribution with a mean of $72 and standard deviation of $34.

Q1. Explain of the variable in the case. Use the statistical expression for the distribution of the variable.

Q2. What proportion of shopper spend less than $50 during a shopping trip? Show your work.

Q3. As the manager of the supermarket, you have decide to award double coupons to your best customers. If you wish to limit double coupon to one-fifth of your customers, what minimum amount must a customer spend during a visit in order to earn double coupons? Show your work.