Question

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

Answer 1

There are a total of 1240 students.

Explanation:

Represent # of boys by b and # of girls by g.

Then b/g = 11:9, and b = g + 124.

Solve this system of equations using substitution:

b 11

----- = ------

g 9

becomes g + 124 11

------------- = -----

g 9

Cross multiplying yields 9g + 124(9) = 11 g, or 9g + 1116 = 11g

Combining the g terms yields:

1116 = 2g

Then g =558.

There are 558 girls. There are 124 more boys than girls: 558+124 = 682 boys.

Altogether there are 558 + 682, or 1240 students.