# Propability question help please! cheers! :-)

• Dec 7th 2012, 06:29 AM
aimsywamesy
Propability question help please! cheers! :-)
2 people are asked (indepently of one another) to choose 2 letters (each) from the letters of the word FRACTION.
Find the probability that: (i) They have no letters in common
(ii) They both choose the same pair of letters.

Ans 15/28
1/28

• Dec 7th 2012, 06:45 AM
Plato
Re: Propability question help please! cheers! :-)
Quote:

Originally Posted by aimsywamesy
2 people are asked (indepently of one another) to choose 2 letters (each) from the letters of the word FRACTION.
Find the probability that: (i) They have no letters in common
(ii) They both choose the same pair of letters.
Ans 15/28 & 1/28

There are $\binom{8}{2}$ to choose two letters.

Thus, there are $\binom{8}{2}$ for the first to pick and $\binom{6}{2}$ for the second to pick totally different letters.
• Dec 7th 2012, 06:53 AM
aimsywamesy
Re: Propability question help please! cheers! :-)
thank you... :-)