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3 years ago

11

the ratio of boys to girls in a classroom is 7:5 4 boys are added to the class the ratio is now 1:1 find the total number of gir

ls in the class

1 answer:

OLEGan [10]3 years ago

7 0

Answer:

14

Step-by-step explanation:

7/5. = x/ x- 4 (the ratio to each other is the same)

cross multiply

7x-28 = 5x

simplified: -2x = -28

divide x and -28 by -2

x= 14

x= # of girls

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