A steakhouse offers 7 sides: baked potato mashed potatoes, fries, broccoli, salad, soup, or mushrooms. If you choose two sides with your meal, how many combinations of two different are possible?

A 14
B 49
C 42
D 21

Respuesta :

For this problem, we can use the formula for combinations, which is:

[tex] \frac{n!}{r!(n-r)!} [/tex], where we have n objects choosing r at a time

[tex] \frac{7!}{2!(7-2)!} = \frac{7!}{2!5!} = \frac{7*6}{2} [/tex]

7*6 is 42, and 42/2 is 21. There are 21 possible combinations

:)