Question

A professor decided he was only going to grade 8 out of 10 HW problems he assigned. How many different groupings of HW problems could he grade?

Answer 1

Answer:

The number of groupings is 45

Explanation:

Given that the professor decided he was only going to grade 8 out of 10 HW problems he assigned.

We want to calculate the number of ways the professor can grade the HW.

Which is a conbination;

$10C8$

Solving we have;

$\begin{gathered} n=10C8=\frac{10!}{8!(10-8)!} \\ n=45 \end{gathered}$

Therefore, the number of groupings is 45