Perms and Combs (1 Viewer)

[IS200]

Hi there.
I was away when my class was taught perms and combs. So if someone wouldn't mind, could they kindly explain the who deal? Coz i'm reading the examples in all my textbooks and i'm lost.
Thanx!!

 

[BlackJack]

Two things:

1) where do you need to start? Fire questions, 'cause lots of us aren't teachers and mighnt' know what to say. Like 'what's the P thingy' or something...

2) Now's not a good time... in many senses (eg. forum's croweded, hard to reply)

Do you know this:
nCr = n! / [ (n-r)! * r! ]
nPr= n! / (n-r)!

 

[spice girl]

Originally posted by IS200
Hi there.
I was away when my class was taught perms and combs.

Looks as if your class taught probability in one day, or you missed school for a few weeks (or coincidentally all the maths periods for a few weeks).

Best thing to do would probably be to look at all the probability questions in the past exams...no time to learn from scratch now...

In the exam, leave the probability questions till last...