the ratio of boys to girls in the class is 5:7. there are 36 children in the class. how many more girls then boys are there in the class?



Answer :

naǫ
x - the number of boys
y - the number of girls

The ratio of boys to girls is 5:7.
[tex]\frac{x}{y}=\frac{5}{7} \\ 7x=5y \\ x=\frac{5}{7}y[/tex]

There are 36 children in the class.
[tex]x+y=36 \\ x=36-y \\ \\ x=x \\ \frac{5}{7}y=36-y \\ \frac{5}{7}y+y=36 \\ \frac{5}{7}+\frac{7}{7}y=36 \\ \frac{12}{7}y=36 \\ y=36 \times \frac{7}{12} \\ y=3 \times 7 \\ y=21 \\ \\ x=36-y=15 \\ \\ 21-15=6[/tex]

There are 6 more girls than boys in the class.