Question

How many different four-person committed can be formed from a group of six boys and four girls?

I don’t understand how to do this problem or set it up at all

Answer 1

This is a combination, not a permutation. That is, the order in which the people are chosen does not matter.
You have 6 boys and 4 girls, or you have 10 people.
Of those you have to choose groups of 4, and since no restriction is given,

C(10,4) or 10!/(6!4!) = 210

(hint: most scientific calculators have a key labelled nCr which will do the arithmetic for you)

Answer 2

Hey, cool, never thought to look for that key :)