## Elementary Algebra

To find the percent change, we use the following formula: percent change = $\frac{New\ amount\ -\ Original\ amount}{Original\ amount}$ $\times$ 100% The original price was 500. The new price is 420. Substituting these values into the formula yields: percent change= $\frac{420-500}{500}$ $\times$ 100% percent change = $\frac{-80}{500}$ $\times$ 100% percent change = -0.16 $\times$ 100% percent change = -16% The percent decrease in the price of the piece of furniture is 16%.