Question

original price is $40 and the sale price is $30. what is the percent decrease?

Answer 1

 $\frac{new - original}{original}$

= $\frac{30 - 40}{40}$

= $\frac{- 10}{40}$

= $\frac{-1}{4}$

= - 0.25

= 25% decrease      (negative sign = decrease, positive sign = increase)

Answer: 25%