1. I find that my average sale (based on going over all my receipts) in my business is $85 with a standard deviation of $21. If I were to randomly sample 81 receipts, what is the probability that my sample mean will be:

1a) within $3 of the population mean?

1b) within $6 of the population mean?

2. A large retail chain is monitoring its customer loyalty program. Their records indicate that 38% of sales (p=0.38) are to loyalty program members. If 500 customer purchases are sampled what is the probability that