What is the original price if you sold it for 8700$ which is 100$ more than two-fifths what you originally paid?

Question

You sold it for 8700$. This was 100$ more than two fifths what you originally paid.

Answer 1

Let P=original price. ⅖ of this is 2P/5, and $100 more is 2P/5+100=8700, because $8,700 was the price it was sold for.

Multiply through by 5: 2P+500=43500. So 2P=43500-500=43000, and P=43000/2=$21,500.

The original price was $21,500.