GATE2015-2-26

The chance of a student passing an exam is $20 \%$. The chance of a student passing the exam and getting above $90 \%$ marks in it is $5 \%$. GIVEN that a student passes the examination, the probability that the student gets above $90 \%$ marks is

1. $\dfrac{1}{18} \\$
2. $\dfrac{1}{4} \\$
3. $\dfrac{2}{9} \\$
4. $\dfrac{5}{18}$

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