Thirty percent of all customers who enter a store will make a purchase. Suppose that six customers enter the store and that these customers make independent purchase decisions. a Let x = the number of the six customers who will make a purchase. Write the binomial formula for this situation. b Use the binomial formula to calculate (a) The probability that exactly five customers make a purchase. (b)What is the probability of not shopping at all? (c) The probability that at least one customer makes a purchase.

Suppose an airline found that about 7% of the people making reservations on a flight from Miami to Denver do not show up for the flight. Suppose that the airline overbooks this flight by selling 226 ticket reservations for an airplane with only 219 seats. Let n = 226 represent the number of ticket reservations. Let r represent the number of people with reservations who show up for the flight. Which expression represents the probability that a seat will be available for everyone who shows up holding a reservation:  Expression I : P(r ≥ 226) Expression II : P(r ≥ 219) Expression III : P(r ≤ 226) Expression IV : P(r ≤ 219) Expression V : P(r = 219)   a. Expression II   b. Expression III   c. Expression I   d. Expression V   e. Expression IV

The probability of a person selling by phone to sell for each call is independent and 0.2. So, what is the probability that he did not sell in exactly 5 calls before making the 2nd sale?

Find the probability of purchasing a ticket with a number whose sums of the first three and last three digits are equal if it has six digits and may be any number from 000000 to 999999.