Answer:
8568
Step-by-step explanation:
You have to choose 5 out of 18, and the order does not matter. So you're looking for the number of combinations, not permutations.
So you have to find 18C5.
nCr = n!/(n-r)!r!
so 18C5 = 18!/13!5!
= (18 * 17 * 16 * 15 * 14 * 13!)/ 13!5!
= 18*17*16*15*14/5*4*3*2*1
= 8568
Hope it helps :)