Question

How many different groups of 3 books can be chosen to read over the summer from a list of 10 books in your English class?

A) 27
B) 45
C) 120
D) 720

Answer 1

The number of different groups of 3 books that can be chosen from a list of 10 books is 120.

Step-by-step explanation:

To calculate the number of different groups of 3 books that can be chosen, we need to use the combination formula. The formula for combinations is C(n, r) = n! / (r! * (n-r)!), where n is the total number of items and r is the number of items selected. In this case, we have 10 books to choose from and we want to choose 3 books. Plugging these values into the formula, we get C(10, 3) = 10! / (3! * (10-3)!) = 10! / (3! * 7!) = (10 * 9 * 8) / (3 * 2 * 1) = 120.

Therefore, the answer is 120 (option C).