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A consignment of 15 record players conta...

A consignment of 15 record players contains 4 defective. The record players are selected at random one by one and examined. The ones examined are not placed back. What is the probability that the `9^(th)` one examined is the last defective.

Text Solution

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The correct Answer is:
`(.^(11)C_(5) xx .^(4) C_(3))/(.^(15) C_(8)) xx (1)/(7)`
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