Question

Assume that the probability of a boy being born is the same as the probability of a girl being born. Find the probability that a family with four children will have the given composition. (Enter your answer to three decimal places.)
Three boys and one girl

Answer 1

\[\dbinom{4}{3}(\frac{1}{2})^4\]

Answer 2

\[\dbinom{4}{3}=4\] is the number of ways you can choose 3 item out of a set of 4, so there are four differnt way you can have one girl and 4 boys
g b b b
b g b b
b b g b
b b b g

Answer 3

what's with (1/2)^4?

Answer 4

(1/2)^4
=1^4/2^4=1/16
2^4 =16

Answer 5

there are two possibilites for each child: b or g
each has probabiltty 1/2
so there are
\[(\frac{1}{2})^4=\frac{1}{16}\] possible sequences of which 4 has three boy and one girl

Answer 6

i understand where u get 1/16 being that there is a half chance for each and theres 4 total in question.. i entered this answer but its not right :(

Answer 7

so its 4ncr3 / 2^4 = .250

Answer 8

thanks!!