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A bag contains 12 counters. 7 of them are white. A counter is taken at random and not replaced. A second counter is taken out of the bag at random. Calculate the probability that only one of the two counters is white​

User CMPE
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First calculate how many counters are 'not white'

12 - 7 = 5

We have 5 counters that are 'not white'

The probability of taking a white counter the first time is 7/12

For the next pick, there would be 1 less of the total counters as it is not being replaced

The probability of then taking a 'not white' counter is 5/11

The other way you could still get one white counter is:

The first counter (non white) probability would be 5/12

The second counter (white) probability would be 7/11

Multiply these values:

7/12 x 5/11 = 35/132

5/12 x 7/11 = 35/132

Add these two values together:

35/132 + 35/132 = 70/132

Your answer is 70/132

Hope This Helps You!

Good Luck (:

Have A Great Day ^-^

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User Magaly
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