Question

Xander spends most of his time with his 10 closest friends. He has known 4 of his 10 friends since kindergarten. If he is going to see a movie tonight with 3 of his 10 closest friends, what is the probability that the first 2 of the friends to show up to the movie are friends he has known since kindergarten but the third is not?

Answer 1

Note that there's a strict order here -> 2 close friends, then 1 non-close friend.

So, picking in order:
probability of picking the first close friend: 4/10
probability of picking the second close friend: 3/9
probability of picking the first non-close friend: 6/8

So, we get 4/10 * 3/9 * 6/8 = 1/10.

Answer 2

Answer:

2/1

Step-by-step explanation: