Learn: Using Percentages

Welcome!Today we'll learn about percentages. Percentages are a way of expressing numbers as parts of 100, and they are widely used in everyday life, such as calculating discounts, interest rates, and proportions.

What are Percentages?A percentage is a fraction or ratio where the denominator is 100. For example, 50% means 50 out of 100, which is the same as 1/2. Percentages are useful for comparing values and working out proportions.

Converting Between Fractions, Decimals, and PercentagesYou can convert between fractions, decimals, and percentages by dividing or multiplying appropriately. For example, to convert a fraction like 3/5 into a percentage, divide 3 by 5 to get 0.6 and multiply by 100 to get 60%.

Percentage Increase and DecreaseTo calculate a percentage increase, multiply the original value by the percentage (as a decimal) and add it to the original value. For a decrease, multiply by the percentage and subtract it from the original value.

Reverse PercentagesReverse percentages help us find the original value before a percentage change. Divide the final value by (1 + percentage change as a decimal) for increases, or (1 - percentage change as a decimal) for decreases.

Using Percentages in Real LifePercentages are used in scenarios such as calculating VAT on purchases, determining interest rates on loans, or figuring out discounts during sales. Knowing how to work with percentages helps you make informed decisions.

Review Time!Great work! You've learned how to calculate percentages, percentage increases, decreases, and reverse percentages. Now let's test your understanding with a few questions.