Learn: Percentage Change

Welcome!Today we'll learn about percentage change. This is a key concept in OCR GCSE Mathematics J560, and it's useful for understanding changes in values in real-life situations like discounts, price increases, or population growth.

What is Percentage Change?Percentage change measures how much a value has increased or decreased compared to its original value, expressed as a percentage. It helps us understand the relative difference between two values.

How to Calculate Percentage ChangeTo calculate percentage change, use the formula:Percentage Change = (Change ÷ Original Value) × 100Where 'Change' is the difference between the new value and the original value.

Calculating Increase and DecreasePercentage change can be positive or negative. A positive percentage change means an increase, while a negative percentage change means a decrease. For example, if a price increases from £20 to £25, the change is £5, and the percentage increase is (5 ÷ 20) × 100 = 25%.

Reverse PercentagesReverse percentages allow us to find the original value when a percentage increase or decrease has already been applied. For example, if a price is £120 after a 20% increase, the original price can be calculated by reversing the percentage increase.

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