I am having problems with this problem. What forumula would I use, and how would I do this problem.

A product has five ways in which it might have a critical defect and ten ways it which it might have a minor defect. In how many different ways may it have (a) one critical defect and two minor defects, (b) three minor defects, (c) two critical defects and four minor defects.

Use the combinations formula for these.

# of ways to choose r items from n items
nCr = n! / r!(n-r)!

for example:
(a) one critical and two minor

5C1 * 10C2
= [ 5! / 1!(5-1)! ] * [ 10! / 2!(10-2)! ]

Thank you for your help.

Another question, in a calculator would it be easier if I just put in 5C1 * 10C2?

yes, it would