Percentage change
A percentage change can be either an increase or a decrease by a percentage
Calculating percentage increase or decrease (Profit or loss%)
Profit percentage
Loss percentage
Finding cost price (before ) and selling price (after)
Do the Problems
- Increase 80kg by 24%
- Decrease 5400 by 20%
- A damaged carpet which cost $180 when new is sold for $100. What is the percentage loss?
- In 2008 the prison population was 1280. In 2010 it was increased by 25%. Calculate the population in the prison now?
- Sana bought a book for $120 at a discount 25% due to damages. What was the marked price of the book?
Simple and Compound Interest
- Simple Interest
- With simple interest, the interest earned is not reinvested. this means that the amount of interest earned each year is unchanged.
- Compound Interest
- With compound interest, the interest earned each year is reinvested. This means that the amount of interest earned each year increases.
Simple Interest
Compound Interest
