Question

Given the set {A, B, C}, how many permutations and combinations are there of this set of 3 objects taken 2 at a time?

Answer 1

A 3 permutations and 6 combinations
B 6 permutations and 3 combinations
C 6 permutations and 9 combinations

Answer 2

I know its either B or C

Answer 3

http://www.mathsisfun.com/combinatorics/combinations-permutations.html

Answer 4

it might help i am not good at permutations

Answer 5

idk. ):

Answer 6

@ZeHanz can u plz help me

Answer 7

\[_nP_r = \frac{ n! }{ (n-r)! } \text{ This is the formula for permuting n objects, r at a time.}\]\[_nC_r = \frac{ n! }{ (n-r)!\,\,r! } \text{ This is the formula the number of combinations of n objects}\]\[\text{taken r at a time.}\]

Answer 8

in your case, how many objects in your set?

Answer 9

Permutations account for all of the different orderings while Combinations account for all of the different groupings.

Answer 10

@katieeeeeeeee: @pgpilot326 is doing a good job here!

Answer 11

can you help me with my newer question please

Answer 12

@me in your new post

Answer 13

On the other hand, the total number of objects is very small. This means you can work out the number of permutations and combinations by reasoning:

For the first object, how many possibilities do you have?
Then, in how many ways can you take the second object?