Percent Change - Calculations

5% = $$5\ \times\ \frac{1}{100}$$ = 0.05

14% = $$14\ \times\ \frac{1}{100}$$ = 0.14

$$percent\ decrease\ =\ \frac{amount\ of\ decrease}{original\ amount}$$

The original amount is 20.

Going from 20 to 5 is a decrease.

From 20 to 5, the amount of decrease is equal to 15 (20-15=5).

So: $$\frac{15}{20}$$ = $$\frac{75}{100}$$ = 75%

The original amount is $50.

The final amount is $60.

Going from $50 to $60 is an increase.

The amount of increase is $10. ($60-$50=$10).

$$percent\ increase\ =\frac{amount\ of\ increase}{original\ amount}$$

So: $$\frac{10}{50}$$ = $$\frac{20}{100}$$ = 20%

Original amount : $5

Final amount : $10

From $5 to $10 is an increase.

Amount of increase : $5

($10 - $5 = $5)

$$percent\ increase\ =\ \frac{amount\ of\ increase}{original\ amount}$$

So: $$\text{}\frac{5}{5}$$ = $$\frac{100}{100}$$ = 100%

Original amount : $10

Final amount : $5

From $10 to $5 is a decrease.

Amount of decrease : $5

($5 - $10 = -$5)

$$percent\ decrease\ =\ \frac{amount\ of\ decrease}{original\ amount}$$

So: $$\frac{5}{10}$$ = $$\frac{50}{100}$$ = 50%

Original amount : $8

Final amount : $10

From $8 to $10 is an increase.

Amount of increase : $2

($10 - $8 = $2)

$$percent\ increase\ =\ \frac{amount\ of\ increase}{original\ amount}$$

So: $$\frac{2}{8}$$ = $$\frac{1}{4}$$ = 25%

Original amount : $10

Final amount : $8

From $10 to $8 is a decrease.

Amount of decrease : $2

($8 - $10 = -$2)

$$percent\ decrease\ =\ \frac{amount\ of\ decrease}{original\ amount}$$

So: $$\frac{2}{10}$$ = $$\frac{20}{100}$$ = 20%

Original amount : 20

Final amount : 30

From 20 to 30 is an increase.

Amount of increase : 10

(30 - 20 = 10)

$$percent\ increase\ =\ \frac{amount\ of\ increase}{original\ amount}$$

So: $$\frac{10}{20}$$ = $$\frac{50}{100}$$ = 50%