Question

What does this mean?

Answer 1

what does what mean

Answer 2

That means the 'number of permutations of 3 in 8'

Answer 3

I do not remember learning this at all.

Answer 4

that is the number ow ways you can take 3 different items from 8 items and the order of arrangement of the 3 matters

Answer 5

A simpler example would be the pemutations of 2 from 1,2 and 3
these would be
1,2
2,1
1,3
3,1
2,3
3,2

There are 6:- 3P2 = 6

Answer 6

ok I am still a little bit confused on this.

Answer 7

what exactly is a permutation and why do we need them. And also what exactly are you looking for when finding a permutation?

Answer 8

The formula for nPr = n! (n-r)!

Answer 9

n! means n factorial

Answer 10

an example of a factorial is 5! = 5*4*3*2*1
- the product of all the numbers from 5 down to 1.

Answer 11

5! = 120

Answer 12

right

Answer 13

so permutations are the factorial of n times the factorial of n minus r?

Answer 14

I think combinations come up more in Math . The difference is that with combinations the order does not matter. 3C2 = 3 because 1,2 is taken to be same as 2,1 etc

Answer 15

yes

Answer 16

Theres a whole branch of Math concerned with permutations and Combinations called
Combinatorics.

Answer 17

nCr = n! / r!(n-r)!

Answer 18

Alright! Thank you. XD

Answer 19

yw