Binomial

Example

a) On this example we will examine the probability a couple who has 8 children and has exactly 5 boys.

b) Next we will look at the probability that they have more than 5 boys.

c) Finally we will look at the probability that they have at most 5 boys.

Assume a .5 chance of having a boy.

Solution can be solved using excel.

a) On this example we will examine the probability a couple who has 8 children has exactly 5 boys.

put this in an excel cell

=binom.dist(5,8,.5,False)

and then hit enter

.21875 would be the answer

b) Next we will look at the probability that they have more than 5 boys.

put this in an excel cell

=1-binom.dist(5,8,.5,True)

and then hit enter

.144531 would be the answer

c) Finally we will look at the probability that they have at most 5 boys.

Assume a .5 chance of having a boy.

put thisin an excel cell

=binom.dist(5,8,.5,True)

and hit enter

.855469 would be the answer

Solve:

a) We will examine the probability that a cat has a litter of 9 kittens and 4 of the kittens are girls.

b) Next we will look at the probability that she has more than 4 girls.

c) Finally we will look at the probability that she has at most 4 girls.

Assume a .5 chance of having a girl.

I am trying to understand how to solve this in bold , the example dosent even help me understand. thank you