Question

When to use ncr and when to use npr ?

Answer 1

If I want to know the number of ways to arrange a set of four unique books out of a total supply of 20 books, I'd use npr.if I want to know the number of ways to make a team of 4 people out of a total group of 20 people, I'd use 20 ncr.

You can mark the brainiest or not, I don't care. It your opinion.
I'm not forcing you Shobhna

Answer 2

Answer:

One must realize the difference thatnCr is the number of ways n objects can be selected in r ways and nPr is the number of ways n objects can be arranged in r ways. In the case of permutations, the order in which the objects are arranged matters