352 divided by 25 = 14.08 so technically 14 r 8
If he put 10 in the bowl and there are 150 cards, the chance for him to win would be 10/150.
now by simplifying it, you get 1/15.
therefore answer is C
Remember, the volume formula of a sphere is

.
Set that equation equal to whatever volume they give you and solve for r.

=

Now solve for r! I know you can do this. If you need help, just comment.
You would need to do 10,125/45 = n, and in which case we just solve.
10,215/45=227, so there are 227 napkins in each box.
Hope this helps and have a nice day:)