1. Which of the following problems is solved by using combinations?

a. Determine the number of different 3-topping pizzas that can be made if 9 toppings are available

b. Determine the number of ways in which 8 different fruits can be distributed among 7 students.

c. Determine the number of arrangements of three different plays if a football team has 6 basic plays

d. Determine the number of ways in which 2 adults and their 3 children can be arranged in a line to have their picture taken.

2.

The number of ways in which a group of 7 students can be seated 5 at a time in a row of 5 desks is 5! 7! 5!x2! 7! 2! There are 6 red balls and 7 black balls in a bag. If two balls are randomly selected. without replacement. from the bag, what is the probability that both balls are red or that both balls are black? 6 l3 2 35 2 169 35 676