There are 7 people in the elevator in a 10story building The

There are 7 people in the elevator in a 10-story building. They are allequally likely to exit on any oor and they are independent of each other.What is the probability that 3 of them will exit on one oor, 2 on another,and the last two on two dierent oors.

Solution

As the events are independent, probability can be calculated as below.

P(3)=3/7=0.43 that is 3 people exit on floor floor

P(2)=2/7=0.29 that is 2 people exit on another floor

P(1)=1/7=0.14 that is probability of last two person each who will exit on different floors.

Here events are independent so events are not affected by previous events and so we have calculated probability for each one of them with same n=7.