Compound Growth and Decay (Edexcel GCSE Maths): Flashcards

Quantities increase over time, with change calculated on the new amount each period

Quantities decrease over time, with change calculated on the new amount each period

Compound: change calculated on new amount each time. Simple: change on original only

$N = N_0(1 + \frac{r}{100})^n$

Final amount after time period

Initial starting amount

Percentage change per time period

Number of time periods

Add % to 100, divide by 100. E.g., 5% increase = 105/100 = 1.05

Subtract % from 100, divide by 100. E.g., 5% decrease = 95/100 = 0.95

1.05

0.95