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The ratio of boy to girls in a class is 3 : 2. There are 15 boys in the class. How many total boys and girls are in the class?
A) 15

B) 23
C) 25
D) 35

Respuesta :

qwertyuiop0987654321
First, let's see what we are told:

1. The ratio of boys to girls is 3:2.  Turn that into an equation

2b=3g2b=3g

2. If two girls are added, the number will be equal

b=g+2b=g+2

Now, substitute the second equation into the first:

2(g+2)=3g2(g+2)=3g
multiply
2g+4=3g2g+4=3g
subtract 2g
4=g4=g

So there are 4 girls and, thus 6 boys
3:2 = 15:10 ( 3x5 = 15 boys; 2x5 = 10 girls)

15+10=25 total boys and girls

answer C) 25