From the past experience, it is known that
the probabilities that he will come by train, bus, scooter or by other means of transport
are respectively 3 1 1
2
, ,
10 5 10and
5 The probabilities that he will be late are 1 1
, , and1
4 3
12,
if he comes by train, bus and scooter respectively, but if he comes by other means of
transport, then he will not be late When he arrives, he is late What is the probability
that he comes by train