Question

The ratio of the price of a used washer to a new one is 1:3. If the new washer cost $720 how much could you resell it used?

Answer 1

Ratio of used to new is 1:3,

So in other words, the value of a used washer is 1/3 of the value of a new washer.

So you can resell a used washer for: $720/3 = $240.

Answer 2

`\bf \begin{array}{ccllll} used&new\\ \text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\ 1&3\\ u&720 \end{array}\implies \cfrac{1}{u}=\cfrac{3}{720}\implies \cfrac{720\cdot 1}{3}=u`