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प्रश्न
A problem is given to three students whose chances of solving it are `1/4, 1/5` and `1/3` respectively. Find the probability that the problem is solved.
उत्तर
Let P(A) =`1/4 , "P"(bar"A") = 1 - 1/4 = 3/4`
P(B) = `1/5 , "P"(bar"B") = 1 - 1/5 = 4/5`
P(C) = `1/3 , "P"(bar"C") = 1- 1/3 = 2/3`
Probability (the problem is solved)
`= 1 - "P"(bar"A")."P"(bar"B")."P"(bar"C")`
`= 1 - 3/4 xx 4/5 xx 2/3`
`= 1 - 2/5 = 3/5`
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