## ksaimouli 2 years ago From 5 employees at a company, a group of 3 employees will be chosen to work on a project. How many different groups of 3 employees can be chosen?

1. ksaimouli

@zepdrix

2. ksaimouli

is their any easy technique it is hard to do mentally

3. ksaimouli

what i do is (3)(3) because 3 people only once

4. zepdrix

So this is probability stuff right? Since order doesn't matter this is a Combination problem, not a Permutation. Understand what I mean by "order doesn't matter"? If Bob, Suzy and then Tom get picked. That's the same as Suzy, Tom and then Bob getting picked. The order they were picked in doesn't matter. The notation can be written like this, $$\large _5C_3$$ Which would be read, "5 choose 3". $\large _nC_r \qquad = \qquad \frac{n!}{r!(n-r)!}$

5. zepdrix

(3)(3)? Hmm maybe there is a simple way to do this like by building a tree, and such. But I'm not really comfortable with this subject of material to explain it that way :\ heh

6. ksaimouli

10

7. zepdrix

Yah that sounds right c: