Answer:
n-k-1
Step-by-step explanation:
n is bigger than k. It asks BETWEEN k and n. so, since n is bigger than k, n-k. since it says BETWEEN, you subtract 1 after that
got it?
=)
oh and the reason i am strict about BETWEEN, is because when it said between, then its discluding k and n.
If it says FROM k and n, then you both include k and n, and that would result of adding 1 instead of subtracting 1.
