Your class room has 32 boys and girls. Two-thirds of the boys and three-fourths of the girls are going on a field trip. There are 9 children left.

Question

What is the ratio of boys to girls in your class?

Answer 1

b = number of boys

g = number of girls

 

b/g = ?

 

Given:

 

b + g = 32

32 - [(2/3)b + (3/4)g] = 9

 

Solve for b and g.

 

b + g = 32 ⇒ b = 32 - g

(2/3)b + (3/4)g = 23 ⇒ 8b + 9g = 276

 

8(32 - g) + 9g = 276

256 + g = 276

 

g = 20

b = 32 - g = 32 - 20 = 12

b/g = 12/20 = 3/5

 

Test these answers.