Another probability question
a pupil travels to school either by MRT or by bus. Th probability that the pupil will be late for school is 1/12 if he travels by MRT and 1/9 if he travels by bus.
a) if he travels by bus on two consecutive days, find the probability that he will be late for school on one out of the 2 days. Give your answer as a fraction reduced to its simplest form.
b) if he is equally likely to travel by MRT or by bus, calculate the probability that he will not be late for school on any given day
c) what is the probability that he will travel by MRT in two successive days and he will not be late on both days? (Given that he is equally likely to travel by a MRT or by bus)
May I have step by step workings please? I don't understand how to do this question!