Question

A math test has 10 questions from which you only have to answer 6 of the questions. How many different ways can you select the 6 questions to answer?

Answer 1

In order to determine the number of ways you can select 6 question to answer, use the following formula:

$C=\frac{n!}{r!(n-r)!}$

where,

n: total number of questions = 10

r = 6

Then, by replacing you obtain:

$C=\frac{10!}{6!(10-6)!}=210$

Hence, there are 210 ways you can select 6 questions to answer.