A man has bunch of 10 keys out of which only one can open the door. He chooses a key at random for opening the door. If at each trial the wrong key is discarded, then the probability that the door is opened on fifth trial is

\[\frac{^{10}{{C}_{5}}}{{{10}^{5}}}\]

A man has bunch of 10 keys out of which only one can open the door. He

1.	A man has bunch of 10 keys out of which only one can open the door. He chooses a key at random for opening the door. If at each trial the wrong key is discarded, then the probability that the door is opened on fifth trial is
A.	\[\frac{1}{2}\]
B.	\[\frac{^{10}{{C}_{5}}}{{{10}^{5}}}\]
C.	\[\frac{1}{10}\]
D.	\[\frac{5!}{10!}\]
Answer» D. \[\frac{5!}{10!}\]

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A man has bunch of 10 keys out of which only one can open the door. He chooses a key at random for opening the door. If at each trial the wrong key is discarded, then the probability that the door is opened on fifth trial is

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