Question

Four coins are tossed. Let z be the random variable representing the number of heads that occur. What is the probability of the least number of times that heads may occur?

Answer 1

For the head to be displayed a tail is not displayed ,

In a case where 4 tails are displayed we then have 0 head

Z=0

When there are 3 tails displayed we have 1 head then it means

Z= 1

In a case where there is 2 tails displayed it also means there is 2 heads displayed hence

Z=2

And in a case where there is only 1 tail displayed the remaining 3 are heads hence

Z=3

And in a case where there is no tail displayed then there are 4 heads displayed meaning

Z= 4.

Hence the Z takes the values {0,1,2,3,4} .

The least number of times that heads may occur is zero with a probability of 1/16.