Q47 of 249 Page 31

Mark the correct alternative in each of the following:

In a college 30% students fail in Physics, 25% fail in Mathematics and 10% fail in both. One student is chosen at random. The probability that she fails in Physics if she has failed in Mathematics is


A = Failing in Physics


B = Failing in Mathematics


P(A) = 30%




P(B) = 25%



→ (Given)


P(A∩B) = 10%




Now we know,






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