Question 129763: In a class, 40% of the students are girls. There are 27 boys in the class. How many girls are there? Answer by ptaylor(2198) (Show Source):
You can put this solution on YOUR website! Let x=number of girls in the class
Then x+27 =total number of students in the class
So our equation to solve is :
40% of (x+27)=x or
0.40(x+27)=x get rid of parens
0.40x+10.8=x subtract 0.40x from each side
0.40x-0.40x+10.8=x-0.40x collect like terms
10.8=0.60x divide both sides by 0.20
x=18-----------------------------number of girls in the class
CK
18+27=45
40% of 45=18
60% of 45=27
