Sagot :
Let:
x=boys
y=girls
1/3y=x
x+y=36
1/3y+y=36
1 1/3y=36
y=36/1 1/3
y=27
1/3y=x
1/3(27)=x
x=9
boys are 9 girls are 27
x=boys
y=girls
1/3y=x
x+y=36
1/3y+y=36
1 1/3y=36
y=36/1 1/3
y=27
1/3y=x
1/3(27)=x
x=9
boys are 9 girls are 27