In a college `3%` 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

Options

A. a) `1/10`
B. b) `1/3`
C. c) `2/5`
D. d) `9/20`

Answer

c) `2/5`

Explanation

Let,


Take `100` students in school


Students (failed in physics) `=3`


Students (failed in math) `=25`


Students (failed in physics and math) `=10`


`P(X)=10/25=2/5`


Hence, correct option is c)