The probability it rains is: p(x) = 20/100 = 0.2
The probability the bus is late is = 8/100 = 0.08
The probability that it rains and the bus is late is = 0.03
The probability the train is late is: p(y)= 0.05
The probability that it rains and the train is late is = 0.01
This is an independent probability
And the formula for expressing two independent events is given below.
[tex]\begin{gathered} X\text{ n Y = p(X) }\times\text{ p(Y)} \\ \text{ = 0.2 x 0.05} \\ \text{ }=\text{ 0.01} \end{gathered}[/tex][tex]\begin{gathered} Since\text{ the two events are independent we have:} \\ p(X\text{/ Y) = p(XnY) / p(Y)} \\ \text{ = 0.01/}0.05 \\ \text{ = 0.2} \end{gathered}[/tex]