GCSE Secondary Maths Age 13-17 - Ratio, Proportion & Rates of Change: Compound Growth and Decay - Explained

The video tutorial explains how to calculate compound interest over two years. In the first year, the interest rate is X percent, and the investment grows from £12,000 to £12,336. The interest rate for the second year is X/2 percent. The tutorial demonstrates how to calculate the interest for each year, find the percentage rate, and use a percentage multiplier for quick calculations. It also discusses the allocation of marks for each step in the problem-solving process.

What was the initial investment amount at the start of the first year?

• £12,336

• £12,508.704

• £12,000

• £336

How much interest was earned at the end of the first year?

• £12,000

• £12,508.704

• £336

• £12,336

What is the interest rate for the second year?

• X/2%

• 2.8%

• 1.4%

• X%

What is the final investment amount at the end of the second year?

• £12,000

• £336

• £12,508.704

• £12,336

How many marks were allocated for calculating the percentage increase using the percentage multiplier?

• Three marks

• Two marks

• One mark

• Four marks