Question

A ruler 30 cm long is broken into two parts in the ratio 8:7. How long are the two parts?

Answer 1

Pro tip: always assign ratios a variable.

So 8x + 7x = 30; 15x=30; x=2

Now plug in x;
8(2)=16 and 7(2)=14
So the pieces are 16 and 14 cm which adds up to 30.