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please tell me the OA...its urgent guys gmat on 11 oct

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by jeegarm » Fri Oct 10, 2008 5:06 am
Q6
A string of 10 lightbulbs is wired in such a way that if
any individual lightbulb fails, the entire string fails. If for
each individual lightbulb the probability of failing during
time period T id 0.06, what is the probability that the
string of lightbulbs will fail during time period T?
A.0.06
B.(0.06)^10
C.1-(0.06)^10
D.(0.94)^10
E.1-(0.94)^10
Answer
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Source: — Problem Solving |

by kris610 » Fri Oct 10, 2008 6:05 am
It would be E. The question says that ALL the light bulbs must SUCCEED if the string is not to fail.

The probability of each individual bulb succeeding is 0.94. Probability that all 10 will succeed is (0.94)^10.

So probability that at least one would fail would be 1 - (0.94)^10.
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by raunekk » Fri Oct 10, 2008 6:37 am
imo:E
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