# math

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in a class, the ratio of boys to girls is 3/4. if there are 12 boys in the class, how many girls are there

• math -

for every 3 boys there is 4 girls
divide 12 by 3 and the answer is 4
multiply 4 by 4

• math -

Set up a proportion. Let x = the number of girls.

3 / 4 = 12 / x

Cross multiply:

3x = 48
x = 16

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