A city council consists of seven Democratsand eight Republicans. If a committee ofseven people is selected, find the probabilityof selecting three Democrats and fourRepublicans.(Type a fraction. Simplify your answer.)

Respuesta :

A city council consists of seven Democrats

and eight Republicans. If a committee of

seven people is selected, find the probability

of selecting three Democrats and four

Republicans.

step 1

we have seven Democrats------> select three Democrats

Find out 3C7

[tex]3C7=\frac{7!}{3!(7-3)!}=35[/tex]

step 2

eight Republicans ------> select four Republicans

Find out 4C8

[tex]4C8=\frac{8!}{4!(8-4)!}=70[/tex]

step 3

Total possible favorable outcomes

35*70=2,450

total possible outcomes

Find out 7C15

[tex]7C15=\frac{15!}{7!(15-7)!}=6,435[/tex]

therefore

the probability is

P=2,450/6,435

simplify

P=490/1,287