Answer :
x=mumber of boys
y=number of girls.
I suggest this system of equations:
x+y=30
x=4y
We can solve this system of equations by susbtitution method.
4y+y=30
5y=30
y=30/5=6
x=4y
x=4*6=24
Answer: there are 6 girls
y=number of girls.
I suggest this system of equations:
x+y=30
x=4y
We can solve this system of equations by susbtitution method.
4y+y=30
5y=30
y=30/5=6
x=4y
x=4*6=24
Answer: there are 6 girls