<PRE><B>Question 129763</B>
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
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