Question

Debbie is borrowing 3 books from her friend who has a collection of 45 books. Which of the following expressions represents the number of ways Debbie can choose a group of 3 books?

a.P(45, 3)
b.C(45, 3)
b.45!

Answer 1

the order of the 3 books does not matter so its the number of combinations of 3 from 45

b is the correct choice

Answer 2

Answer: b.C(45, 3)

Explanation:

Given: Debbie is borrowing 3 books from her friend who has a collection of 45 books.

Therefore, the number of ways Debbie can choose a group of 3 books will be equal to the number of combinations of selecting 3 books from 45 books.

i.e. The number of ways Debbie can choose a group of 3 books=
`C(45, 3)`