Question

Find percent of change

original : 72 and new: 36

Answer 1

Step1

Original:72

New:36

Since the new amount is less than the original, this is a percent of secrease.

The amount of change = Original Amount - New Amount.

The amount change = 72 -36 = 36.

Step2

Let r be the percentage of decrease.

Use the original number, 72 as the base.

The percent proportion is

                change  → 36/72=r/100

                origina amouT

Step3

To solve for r, first find the cross products.

36.100=72r

3600=72r                                   (Multiply: 36*100=36000)

3600/7200=72.r/72                  (Divided cach side by 72)

the percent of change is a percent of decrease.

The percentage of decrease by 50%.