# Repeated percentage change

## Lesson details

### Key learning points

1. In this lesson, we will learn about the cumulative effect of repeated percentage changes.

### Licence

This content is made available by Oak National Academy Limited and its partners and licensed under Oak’s terms & conditions (Collection 1), except where otherwise stated.

## Video

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## Worksheet

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## Starter quiz

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### 5 Questions

Q1.
If 75% of my number is 150, what is my number?
11,250
112.5
225
Q2.
If I buy a car in a 20% off sale and it costs £30,000, how much did the car originally cost?
£6,000
37,500
6,000
Q3.
If I decreased the amount I paid for my car insurance by 90% to £36.50 per year, how much did I pay previously for my car insurance?
£3.65
£32.90
£36.50
Q4.
If a jumper was marked as 56% off and costs £50 now, then 44% of the original cost of the jumper is equal to £50
False
Q5.
If I know something costs £2.10 in a 30% off sale, then i would do £2.10 = 70% and scale accordingly to get that 100% = £3 to find the original amount.
False

## Exit quiz

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### 5 Questions

Q1.
What would the value of £300 become if it grew by 5% and then another 5%?
£305
£310
£330
Q2.
If an antique appreciates by 6% per year for 11 years, the decimal multiplier would be 1.06^11.
False
Q3.
If I want to find the 'original' price of something that is currently in a sale and has 40%, I always need to find 100% of the amount to work out the original price.
False
Q4.
If I start with a number, increase it by 30% and then decrease it by 30%, I get back to the original number.