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;
[tex]10C8[/tex]Solving we have;
[tex]\begin{gathered} n=10C8=\frac{10!}{8!(10-8)!} \\ n=45 \end{gathered}[/tex]Therefore, the number of groupings is 45