Exercise 23 Page 166

Let's start by recalling that a percent of change is a ratio that compares the change in quantity to the original amount. If the original quantity is increased, then it is called a percent of increase. If the original quantity is decreased, then it is called a percent of decrease. To determine the percent of change, we can use the following formula. Percent of change =Amount of change/Original amount In this case, the original quantity is 35 birds, and the new quantity is 45 birds. We can find the amount of change by subtracting the less value from the greater one. Amount of change = 45 - 35 = 10 Now let's use the formula to find the percent of change.

To write the decimal as a percent, we need to move the decimal point two places to the right and write the percent symbol.

We found that the percent of change is about 29 %. Finally, let's state whether the percent of change is an increase or a decrease. To do so, we need to compare the original quantity with the new quantity. ccc Original quantity & & New quantity [0.5em] 35birds & < & 45birds Since the new quantity is greater than the original quantity, this is a percent of increase.