Question

Tina must select and answer in any order three of seven

Answer 1

Answer:

Tina can select and answer the essay questions on her test in 35 ways.

Step-by-step explanation:

The order in which she chooses the questions is not important. For example, choosing questions 1, 3 and 7 is the same as choosing 7, 3 and 1. So we use the combinations formula to solve this question.

Combinations formula:

$C_{n,x}$ is the number of different combinations of x objects from a set of n elements, given by the following formula.

$C_{n,x} = \frac{n!}{x!(n-x)!}$

In this question:

Three questions from a set of 7. So

$C_{7,3} = \frac{7!}{3!(7-4)!} = 35$

Tina can select and answer the essay questions on her test in 35 ways.