Consider the following events,
M = selected student is a male
F = selected student is a female
A = selected student has an A
The probability that the student is a male, given that he/she has an A, is given by,
[tex]P(\frac{M}{A})=\frac{P(M\cap A)}{P(A)}[/tex]This can be evaluated as,
[tex]\begin{gathered} P(\frac{M}{A})=\frac{P(M\cap A)}{P(A)} \\ P(\frac{M}{A})=\frac{n(M\cap A)}{n(A)} \\ P(\frac{M}{A})=\frac{2}{4+2} \\ P(\frac{M}{A})=\frac{2}{6} \\ P(\frac{M}{A})=\frac{1}{3} \end{gathered}[/tex]Thus, the probability that the student is a male, is 1/3 , given that he/she has an A.