Permutations & Combinations

Front

What is a permutation?

Back

A permutation is an arrangement of objects in a specific order. The order matters.

Front

What is a combination?

Back

A combination is a selection of objects where the order does not matter.

Front

How do you calculate permutations of n objects taken r at a time?

Back

The formula is P(n, r) = n! / (n - r)!.

Front

How do you calculate combinations of n objects taken r at a time?

Back

The formula is C(n, r) = n! / (r! * (n - r)!).

Front

What is the factorial of a number?

Back

The factorial of a number n (denoted as n!) is the product of all positive integers up to n.

Front

Calculate 5!

Back

5! = 5 × 4 × 3 × 2 × 1 = 120.

Front

If there are 8 pies, how many ways can you choose 3?

Back

C(8, 3) = 56.

Front

If there are 8 glasses, how many ways can you arrange them?

Back

P(8) = 8! = 40320.

Front

How many ways can a coach choose 5 players from 11?

Back

C(11, 5) = 462.

Front

What is the difference between permutation and combination?

Back

Permutation considers order; combination does not.