there are 5 more girls than boys in a class. if 2 boys join the class, the ratio of girls to boys is 5:4. find the number of girls in the class.
The answer I had was x=10
B=x,two boys jointed boys became B=x+2,G=x+5.The ratio is girls to boys ie g:b;x+5:x+2=5:4
X+5/x+2=5/4 using cross multiply
4(x+5)=5(x+2)=4x+20=5x+10
5x-4x=20-10
X=10
The answer had was x=10
B=x,two boys jointed boys became B=x+2,G=x+5.The ratio is girls to boys ie g:b;x+5:x+2=5:4
X+5/x+2=5/4 using cross multiply
4(x+5)=5(x+2)=4x+20=5x+10
5x-4x=20-10
X=10
right now:
boys --- x
girls --- x+5
2 boys join class:
boys = x+2
girls = x+5
(x+2)/(x+5) = 5/4
solve for x , sub into x+5
By going through the second and third solution, i believe it is have a bit error's
x+12/x+2=5/4
4x+48=5x+10
4x-5x=10-48
x=38
Therefore the number of girls is
38+5+7=50