Combinations Formula

The number of different arrangements for a given set. Order does not matter.

C=combinations

n=objects in set

r=subset, or number of objects chosen for combination Eg.you have 10 different fruits, but can only take 2 fruits. The "2 fruits" is the r.

!=factorial- multiply a number to the one below it, and that does the same to the one below it etc. Eg. 3!=3*2*1=6

Permutations Formula

The number of different unique arrangements in a given set. Order DOES matter.

P=permutations

n=objects in set

r=subset, or number of objects chosen for combination Eg.you have 10 different fruits, but can only take 2 fruits. The "2 fruits" is the r.

!=factorial- multiply a number to the one below it, and that does the same to the one below it etc. Eg. 3!=3*2*1=6