He can only pick 7 different groups because 2 times 7 is 14, and there are 15 people in all.
Hope this helps. c:
19 songs per album
djdjdjd djdjdjd jdjdjdjdkdkdkdkdkdkdjxndmdmdjddjjdjddjdjdjdjdjfj or 19/1
So there is 15 different outcomes which we want 6 of them 2, 3, 5, 7, 11 all prime numbers so a 6/15 chance we’d pull a prime number
6/15 or 40% chance we’d pull a prime number out of the bag