View Full Version : QR problem...


busdent
09-10-2006, 09:17 PM
A panel of 3 people is to be selected from a group of 5 people. How many different possible panels are there?

a. 10
b. 12
c. 15
d. 20
e. 60

I thought that answer would be 20 but Kaplan shows the answer being 10.

Can you please explain? thanks

_veo_
09-10-2006, 10:07 PM
5!/3!2! = 10

When you want to make a smaller group from a bigger one and the order doesn't matter, you use this formula:

K!/N!(K-N)!
Where K is the big group from where you are taking the little group, which is N
Hope it helps!

busdent
09-10-2006, 11:39 PM
5!/3!2! = 10

When you want to make a smaller group from a bigger one and the order doesn't matter, you use this formula:

K!/N!(K-N)!
Where K is the big group from where you are taking the little group, which is N
Hope it helps!

thanks a lot..I kept doing 5!/3!