A doctor claims that 60% of the patients he examines are allergic to some type of weed.what is the probability that (i) Exactly three of his next four patients are allergic to weeds.

A doctor claims that 60% of the patients he examines are allergic to some type of weed.what is the probability that (ii)None of his next four patients is allergic to weeds.

A doctor is to visit a patient. 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. 3/10, 1/5, 1/10 and 2/5 . The probabilities that he will be late are 1/4, 1/3 , and 1/12 , 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 he probability that he comes by train?

A patient approaches a doctor with a problem that he was not able to sleep for the last 6 months. The doctor said that it may be due to the defect in the relay centre of his brain and advised him to take sedative pills. a) Which part of brain is described here as relay centre ? b) What are the actions of sedative pills in body ?