Chapter 4 - Proportions, Percents, and Solving Inequalities - 4.2 - Percents and Problem Solving - Problem Set 4.2 - Page 156: 50

The percent change in the number of employees from July to August is -40%. It is a percent decrease.

The number of people employed in August was 240. This was 160 people less than the number of people employed in July, which means that in July there were employed 240 + 160 = 400 people. To find the percent change, we use the following formula: percent change = $\frac{New\ amount\ -\ Original\ amount}{Original\ amount}$ $\times$ 100% The previous amount of people was 400, and the new amount was 240. Substituting these values into the formula yields: percent change = $\frac{240\ -\ 400}{240}$ $\times$ 100% percent change = $\frac{-160}{400}$ $\times$ 100% percent change = -0.4 $\times$ 100% percent change = -40% Because the percent change is a negative number, it is a percent decrease.