Fractions problem solving

Question

a Grade 6 class had a debate on: Should school uniforms be compulsory in school?

 

before the debate started, 1/5 of the class were FOR the idea that uniforms should be compulsory.

 

after listening to both sides of the argument during the debate, 8 children changed sides.

 

the fraction for school uniform to be made compulsory is now 3/7.

 

how many children are there in the class together?

Answer 1

I assume the 8 changed from AGAINST to FOR, since 3/7 > 1/5.

 

x = total number of children in the class

 

Start with 1/5 FOR, add 8, and end up with 3/7 FOR.

 

(3/7)x = (1/5)x + 8

 

Solve for x and get x = 35.