Question

`

Answer 1

If the price varies directly with the length, we can write
\[P = k*l\] where P is the price, l is the length, and k is a constant. You know that a 20 inch string costs $360. Use that to find k. Use the updated equation to find the length of a string that costs $288. You'll need to rearrange the equation for price to give you an equation for length in terms of price.

Answer 2

Or, do it with proportions.