answer is 0.9965

but i dont know how to get there

Please answer 22c

22. You have decided to start a whale watching business in Tofino and you would like to make sure that your boat doesnt have any empty seats. Since some the tickets will be purchased online, you estimate 85% of those tickets will be used and the rest returned for refunds. Your boat holds 7 customers and you have decided to sell 8 tickets per trip.

(a) What is the probability exactly 7 people will show up for a whale watching trip?

(b) What is the probability you will have at least one empty seat on your boat?

(c) Your accountant estimates you will need to have 820 paying customers for the season to break even. What is the probability you will at least break-even if you sell 1000 tickets? (assume none of your trips are overbooked).