Percentages

Front

What is a percentage?

Back

A percentage is a way of expressing a number as a fraction of 100. It is often used to compare proportions.

Front

How do you calculate a percentage of a number?

Back

To calculate a percentage of a number, multiply the number by the percentage (in decimal form). For example, to find 20% of 50, calculate 50 x 0.20 = 10.

Front

What does a 25% discount mean?

Back

A 25% discount means that the price is reduced by 25 out of every 100 units of currency. For example, if an item costs $100, a 25% discount would reduce the price to $75.

Front

How do you find the new price after a discount?

Back

To find the new price after a discount, subtract the discount amount from the original price. For example, if an item costs $100 and has a 20% discount, the discount is $20, making the new price $80.

Front

What is 80% of 90?

Back

80% of 90 is calculated as 90 x 0.80 = 72.

Front

What is the formula to calculate percentage error?

Back

Percentage error is calculated using the formula: (|actual value - expected value| / expected value) x 100%.

Front

If a tarp is 28.4 meters long, what is the acceptable range if the ideal length is 26 meters with a 13% error?

Back

The acceptable range is 26 meters ± 3.38 meters (13% of 26), which means the tarp should be between 22.62 meters and 29.38 meters.

Front

How do you increase a number by a percentage?

Back

To increase a number by a percentage, multiply the number by the percentage (in decimal form) and add that to the original number. For example, to increase 100 by 10%, calculate 100 + (100 x 0.10) = 110.

Front

What is the total reading time if Yori reads for 450 minutes and aims to read 10% more next month?

Back

If Yori reads 450 minutes this month and aims to read 10% more next month (which is 45 minutes), her total reading time will be 450 + 495 = 945 minutes.

Front

What is the relationship between fractions and percentages?

Back

Fractions can be converted to percentages by multiplying the fraction by 100. For example, 1/4 is 0.25, which is 25%.