tusharvk wrote:

x2suresh wrote:

Ibodullo wrote:

x2suresh, can you please explain your answer? Thanks!!!

10 - Republicans

10 - Democrates

Answ= No of Ways choose 3 R out of 10 R * No of Ways choose 3 D out of 10 D

why would be 10x9x8x10x9x8 wrong?

You are using Permutations.. that's valid if order matters..

e.g. consider you have group of 3 repuplicans.. R1 R2 R3

how many ways you will select 2 Repulicans out of 3

Is it 3P2 or 3C2??? will see..

Your answer = 3P2 = 3*2 =6 ways

A1 A2 --A2 A1 <duplicate>

A2 A3 --A3 A2 <duplicate>

A3 A1 --A1 A3 <duplicate>

My answer = 3C2 = 3*2/2! = 3 ways.

A1 A2 =A2 A1

A2 A3 =A3 A2

A3 A1 =A1 A3

Did you get it

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