Respuesta :
Divide 42 by three, since you have three groups. Two of boys and one of girls.
42/3=14
14*2=28
14 girls and 28 boys
42/3=14
14*2=28
14 girls and 28 boys
No of girls = x
No of boys = 2x
x+2x=42
3x=42
x=42/3=14
Therefore there are 14 girls