# probability

• December 10th 2008, 09:49 PM
sftball
probability
A couple has six children. Assuming boys and girls are equally likely, what is the probability that they have fewer than 4 girls?
• December 10th 2008, 10:08 PM
mr fantastic
Quote:

Originally Posted by sftball
A couple has six children. Assuming boys and girls are equally likely, what is the probability that they have fewer than 4 girls?

Let X be the random variable number of girls.

X ~ Binomial(n = 6, p = 1/2).

Calculate $Pr(X < 4) = 1 - \Pr(X \geq 4)$.
• December 11th 2008, 09:01 AM
sftball
Thankyou...(Nod)