A, B and C shot to hit a target. If A hits the target 4 times in 5 trails, B hit it 3 times in 4 trials and C hits 2 time in 3 trials; what is the probability that the target is hit by a least 2 person?

Explanation

`P(A)=frac{4}{5}, P(B)=frac{3}{4}, P(C)=frac{2}{3}`

`P(bar{A})=frac{1}{5}, P(bar{B})=frac{1}{4}, P(bar{C})=frac{1}{3}`


`P` (at least two hit the target)


`=P(A cap B cap C)+P(A cap B cap bar{C})+P(bar{A} cap B cap C)+P(A cap bar{B} cap C) `
`=frac{4}{5} cdot frac{3}{4} cdot frac{2}{3}+frac{13}{30} quad text [[Using (a)]] `

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