Thursday Friday and Saturday are the busiest nights at the J

Thursday, Friday and Saturday are the busiest nights at the Jopper bar. Police records show that on 12 of the last 50 Thursdays, 15 of the last 50 Fridays, and 16 of the last 50 Saturdays they were summoned to deal with a disturbance at the bar. Construct a tree diagram and use it to find the probability that over the next Thursday, Friday and Saturday nights there will be:

A) No trouble

C) Trouble o one night only

E) Trouble on two nights only

Assume that events on any one night are independent of events on any other night.

Solution