Question

at school number of boys : number of girls =11:9
there are 124 more boys than girls
work out the total numbers of students at the school

Answer 1

Step-by-step explanation:

let number of boys be X and number of girls be Y then according to question it is given:

X:Y=11:9,and (eqn.1)

X=Y+124

now put X=Y+124 in eqn.1

we get:

Y+124:Y=11:9

by cross multiplicationwe get:

9(Y+124)=11(Y)

now solving this equation we get:

Y=62

since number of girls=Y=62

hence,number of boys=X+124=62+124=186

since total number of students in that school will be

number(boys)+number(girls)

=62+186

=248.

hope it helps you

Answer 2

Answer: 1240

Step-by-step explanation:

b/g = 11/9    so  b = 11g/9

g + 124 = b     so  g + 124 = 11g/9   Multiply both sides by 9

9g + 9*124 = 11g     subtract 9g from both sides

9*124 = 2g    divide both sides by 2

 g = 9*124/2   or g = 9*62   so  g = 558

 Hence b = 558+124   or  b = 682

 Total students = 558 + 682 = 1240