Question

The ratio of boys to girls is 7:1. If there are 84 more boys than girls , work out how many boys there are

Answer 1

98

Explanation:

x: Boys

y: Girls

`\left \{ {{x=y+84} \atop {x=7y}} \right.`

Insert second equation into first one:

`7y=y+84\\`

`6y=84`

`y=14\\`

then substitute y value into second equation:

`x=7*14`

`x=98`