Perms

[MrBen5]

Does anyone know how perms work?
As in if i had 10 numbers, how many perms of 3 numbers would there be? And how many perms of 4 numbers would there be?
Bearing in mind, its for the lotto, so it doesnt matter what order they are in, so that should reduce the amount down by far.
cheers...

[R1Geezer]

well you don't want perms for the lottery as the order is not important, what you want is combinations. If you had 10 numbers then there are:

(10x9x8x7)/(1x2x3x4) cmbinations so 5040/24 = 210 sets of 4 numbers
(10x9x8)/(1x2x3) = 720/6 = 120 sets of 3 numbers

[MrBen5]

Hmmm, cheers.
I dont understand how there can be more sets of 4 number ones though???

[R1Geezer]

why is that surprising? there are 252 ways of choosing 5 numbers!

the forumula for the number of combinations of X from N is thus:

N! / ((N-X)!X!)

[MrBen5]

Hmmm, i suppose it doesnt make sense to me.
I know there is a formula, but surely the number of combo's decrease as you pick more from the 10 numbers.
Can you tell me how many combos there are if there was 9 from 10?

[novalis]

Any 9 from 10 = 10.
It goes up then comes back down so th figures given already are correct.

[R1Geezer]

I'd stay away from Maths if I was you mate!

[weggiewabbit]

As stated above,

Any 3 from 10 = 120
Any 4 from 10 = 210
Any 5 from 10 = 252
Any 6 from 10 = 210 (same as leaving any 4 out)