SOLUTION: a box contains 6 white counters and 5 yellow counters. a counter is picked at random from the box and replaced. a second counter is then picked and a third counter is also picked.

Question 762630: a box contains 6 white counters and 5 yellow counters. a counter is picked at random from the box and replaced. a second counter is then picked and a third counter is also picked. find the probability that a) the third counter is white given that the first counter is white b) all the counters are yellow c) the counters are of different colours
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
a box contains 6 white counters and 5 yellow counters. a counter is picked at random from the box and replaced. a second counter is then picked and a third counter is also picked. find the probability that
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Note: Because of "replacement" the events are independent.
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a) the third counter is white given that the first counter is white
The 3rd selection is not affected by the 1st selection.
Ans: 6/11
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b) all the counters are yellow
Ans: (5/11)^3
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c) the counters are of different colours
Note: With 3 selections there must be two counters of the same color.
Ans: 0
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Cheers,
Stan H.
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