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Mr. Karanja owns a bicycle which he sometimes rides to go to work. Out of the 21 working days in a month, he only rides to work for 18 days. If he rides to work, the probability that he is bitten by a rabid dog is
#4/15# otherwise its only #1/13#. When he is bitten by the dog, the probability that he will get treatment is #4/5# and if he does not get treatment the probability that he will get rabies is #5/7#.
(a) Draw a tree diagram to show the events
(b) Using the tree diagram in (a) above, determine the probability that
(i) Karanja will not be bitten by a rabid dog
(ii) He will get rabies
(iii) He will not get rabies if he does not get treatment