question_answer

A person goes to office either by car, scooter, bus or train, the probability of which being \[\frac{1}{7},\]\[\,\frac{3}{7},\] \[\frac{2}{7}\]and \[\frac{1}{7}\] respectively. Probability that he reaches office late, if he takes car, scooter, bus or train is \[\frac{2}{9},\] \[\frac{1}{9},\] \[\frac{4}{9}\] and \[\frac{1}{9}\] respectively. Given that he reached office in time, then what is the probability that he travelled by a car.

A)  \[\frac{9}{7}\]                         

B)  \[\frac{2}{7}\]

C)  \[\frac{3}{7}\]                         

D)  \[\frac{5}{7}\]

E)  None of these