A survey released by the National Association of Convenience Stores (NACS) indicated that 70% of gas purchases paid for at the pump were made with a credit or debit card.
a. Indicate the type of probability assessment method that NACS would use to assess this probability.
b. In one local store, 10 randomly chosen customers were observed. All 10 of these customers used a credit or a debit card. If the NACS statistic applies to this area, determine the probability that 10 out of 10 customers would use a credit or debit card.
c. If 90% of gas purchases paid for at the pump were made with a credit or debit card, determine the probability that 10 out of 10 customers would use a credit or debit card.
d. Based on your answers to parts b and c, does it appear that a larger percentage of local individuals use credit or debit cards than is true for the nation as a whole? Explain.