# mathematics

there are 5 more girls than boys in a class. if 2 boys join the class, the ratio of girls to boys is 5:4. find the number of girls in the class.

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1. right now:
boys --- x
girls --- x+5

2 boys join class:
boys = x+2
girls = x+5

(x+2)/(x+5) = 5/4
solve for x , sub into x+5

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2. x=17

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3. x = 17

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B=x,two boys jointed boys became B=x+2,G=x+5.The ratio is girls to boys ie g:b;x+5:x+2=5:4
X+5/x+2=5/4 using cross multiply
4(x+5)=5(x+2)=4x+20=5x+10
5x-4x=20-10
X=10

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2. 👎
B=x,two boys jointed boys became B=x+2,G=x+5.The ratio is girls to boys ie g:b;x+5:x+2=5:4
X+5/x+2=5/4 using cross multiply
4(x+5)=5(x+2)=4x+20=5x+10
5x-4x=20-10
X=10

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2. 👎
6. x+12/x+2=5/4
4x+48=5x+10
4x-5x=10-48
x=38
Therefore the number of girls is
38+5+7=50

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7. By going through the second and third solution, i believe it is have a bit error's

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