Question

You can answer any 10 questions from a total of 12 questions on an exam. In how many different ways can you select the questions?

Answer 1

`66` different ways

Explanation:

Because order doesn't matter in this problem, we use the combination formula.

We are picking `10` from a set of `12`, so `n = 12` and `r = 10`.

`color(white)("two")_nC_r = (n!)/((n - r)!r!) = (12!)/((12 - 10)!10!) = 66`

Hence, there are `66` different ways you can select the questions.

Hopefully this helps!