In a college, 30% students fail in physics, 25% fail in Mathematics and 10% in both. One student is choosen at random. The probability that she fails

Monjur Alahi

In a college, 30% students fail in physics, 25% fail in Mathematics and 10% in both. One student is choosen at random. The probability that she fails in physics, if she has failed in Mathematics is
A. `1/10`
B. `2/5`
C. `9/20`
D. `1/3`


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Salim Ahmed Kawsar

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Here, `P((ph))=30/300=3/10,P((M))=25/100=1/4`
and `P((McapPh))=10/100=1/10`
`therefore P((Ph)/M)=(P(PhcapM))/(P(M))=(1//10)/(1//4)=2/5`

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