SOLUTION: In a class, 40% of the students are girls. There are 27 boys in the class. How many girls are there?

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

Hope this helps---ptaylor

RELATED QUESTIONS
There are 40 students in class .three fifth of the students are boys .how many girls (answered by Alan3354)

The ratio of boys to girls in a class is 3:5. There are 40 students in the class. How... (answered by dkppathak)

In a class of 330 students, there are 60 more girls than boys. How many girls are in the... (answered by erica65404)

there are 48 students in a class. twice more boys than girls. how many girls are there in (answered by amarjeeth123)

40% of the students in the class are boys. There are 18 less boys than girls in the... (answered by ewatrrr)

if 40% of the students in the class are boys and if there are 15 girls in the class then... (answered by ankor@dixie-net.com,unlockmath)

The ratio of boys to girls in a class is 3:5. There are 40 students in the class. How... (answered by josgarithmetic)

There are 27 girls in class. 1/4 of the class is boys. How manay students are boys? (answered by stanbon)

In a class of 40 pupils, there are 24 boys and the rest are girls. How many percent more... (answered by Edwin McCravy)