Answer:
20
Step-by-step explanation:
This is the formula for a combination. Substitute the values and evaluate the expression.
[tex]\frac{n!}{r!(n-r)!}\\\\\frac{(6)!}{(3)!(6-3)!}\\\\\frac{(6)!}{(3!)(3!)}\\\\\frac{(6\cdot5\cdot4\cdot3\cdot2\cdot1)}{(3\cdot2\cdot1)(3\cdot2\cdot1)}\\\\\frac{720}{(6)(6)}\\\\\frac{720}{36}\\\\ 20[/tex]