50
« on: November 20, 2010, 01:58:00 pm »
I had to go google factorial function and nCr function because your explanations were kind of muddled.
And then your placing of ncr(10,3) made me think somehow you were trying to multiply nCr by (10,3)before I thought about how the heck you would go about multiplying that and decided that you must have typoed.
Then I spent about twenty minutes trying to figure out how you got (6,2)*(24,5)=637560
Then I remembered factorial function, and.... that didn't help me. Still trying to figure out how to use N!/(n!*(N-n)!)
I had to trial and error it.
6!/(2!*(24!-5!)!)
I mentally factorial functioned 6 getting 720
2 got me 2.
I had to a calculator with 24, but my calculator doesn't have a factorial function but I eventually got 620,448,401,733,239,439,360,000
5 got me 120
720/(2*(620,448,401,733,239,439,360,000-120)!)
Distributive property.
1240896803466478878720000-240=1240896803466478878719976
Lets just say that this far from helped.
So back to this.
ncr(6,2)*ncr(24,5)=637560
Multiplying them all together only got me 1,440.
So suffice to say I need further elaboration on this to understand it.