probability

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probability

by fightthegmat » Tue Sep 08, 2009 10:41 am
Six cards numbered from 1 to 6 are placed in an empty bowl. First one card is drawn and then put back into the bowl; then a second card is drawn. If the cards are drawn at random and if the sum of the numbers on the cards is 8, what is the probability that one of the two cards drawn is numbered 5 ?
A. 1/6
B. 1/5
C. 1/3
D. 2/5
E. 2/3

How to crack this

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by tom4lax » Tue Sep 08, 2009 11:04 am
Why wouldnt it technically be 6 possibile outcomes?

2,6
6,2
3,5
5,3
4,4
4,4

so 1/3?

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by bharathh » Tue Sep 08, 2009 11:06 am
4,4 can only occur one way. Order doesn't matter in this case unlike the other cases

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by tom4lax » Tue Sep 08, 2009 11:16 am
got it, thanks.