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Assume that on a n average on telephone ...

Assume that on a n average on telephone number out of 15 called between 2 P.M. and 3 P.M. on week days s busy. What is the probability that if six random selected telephone numbers are calld, at least 3 of them will be?

Text Solution

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The correct Answer is:
i) `(14^(4))/(15^(5))` ii) `(20(14)^(3)+15(147)^(2)+6(14)+1)/(15^(6))`
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