The ratio of boys to girls is 3 to 7. If there are 20 more girls than boys, how many boys are there?
2 answers
There are 17 boys
Not quite.
b/g = 3/7
g = b+20
b = g-20
= 7b/3 - 20
4b/3 = 20
b = 15
check: 15/35 = 3/7
b/g = 3/7
g = b+20
b = g-20
= 7b/3 - 20
4b/3 = 20
b = 15
check: 15/35 = 3/7
1 answer