Question 1015936
There are 200 students in a school.  There are 20 more boys than girls.  Find the number of girls and boys in the school
Let b and g be the number of boys and girls.
Thus we have
b + g = 200  and
b = g + 20
Now substitute the second equation into the first and get
g+20 + g = 200
2g + 20 = 200
2g = 180
g = 90 girls
b = g + 20 = 110 boys