SOLUTION: In Mr Kings class, there are 2 girls for every 3 boys. If he has 30 children in his class, how many are girls?

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Question 859722: In Mr Kings class, there are 2 girls for every 3 boys. If he has 30 children in his class, how many are girls?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Let x = number of girls


So there are 30-x boys


2%2F3+=+x%2F%2830-x%29


2%2830-x%29+=+3x


60-2x+=+3x


60+=+3x%2B2x


60+=+5x


60%2F5+=+x


12+=+x


x+=+12


There are 12 girls in the class.