1. Reverse Percentage Change – Non-Calculator – Demonstration
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2. How many crisps were there in a packet before the increase?
50% EXTRA FREE!
Now 300g!
How many crisps were there in
a packet before the increase?
100% = 200g
100%
50%
50%
100g
50%
100g
50%
100g
300g

3. How many sweets did you get
50% EXTRA FREE!
Now 240 sweets!
How many sweets did you get
before the increase?
100% = 160 sweets
100%
50%
50% 80
50% 80
50% 80
240

4. How big was the burger before the increase? 100% = 120g 100% 25% 25%
25% BIGGER!
Now 150g!
How big was the burger
before the increase?
100% = 120g
100%
25%
25% 30
25% 30
25% 30
25% 30
25% 30
150

5. How big was the drink before the increase? 100% = 240ml 100% 25% 25%
25% BIGGER!
Now 300ml!
How big was the drink
before the increase?
100% = 240ml
100%
25%
25% 60
25% 60
25% 60
25% 60
25% 60
300

6. How big was the juice carton
20% EXTRA FREE!
Now 240ml!
How big was the juice carton
before the increase?
100% = 200ml
100%
20%
20% 40
240

7. a packet before the increase?
20% EXTRA FREE!
Now 42 in a packet!
How many sweets were in
a packet before the increase?
100% = 35 sweets
100%
20%
20% 7 42

8. How big was a bar of chocolate
10% EXTRA FREE!
Now 66g!
How big was a bar of chocolate
before the increase?
100% = 60g
100%
10%
10% 6 66

9. How big was the cupcake before the increase? 100% = 80g 100% 10% 88
10% BIGGER!
Now 88g!
How big was the cupcake
before the increase?
100% = 80g
100%
10%
10% 8 88

10. How big was the chocolate bar
5% BIGGER!
Now 84g!
How big was the chocolate bar
before the increase?
100% = 80g
100% 5% 4 84
84 ÷ 21 = 4g

11. How big was the lollipop
5% BIGGER!
Now 126g!
How big was the lollipop
before the increase?
100% = 120g
100% 5% 6
126
126 ÷ 21 = 6g

12. How big was a portion of fries
15% BIGGER!
Now 69g!
How big was a portion of fries
before the increase?
100% = 60g
100%
15% 3 69
69 ÷ 23 = 3g

13. How big was the chocolate bar
15% BIGGER!
Now 138g!
How big was the chocolate bar
before the increase?
100% = 120g
100%
15% 6
138
138 ÷ 23 = 3g

14. 2) Find the original size of these items before the increase.
100%
50%
50% BIGGER!
Now 90g!
1) How big was the burger
before the increase?
Was: 60g 90
2) Find the original size of these items before the increase. a)
50% BIGGER!
Now 120g! b)
25% EXTRA!
Now 75g! c)
20% MORE!
Now 96ml!
Was: 80g
Was: 60g
Was: 80ml
20% EXTRA!
Now 60ml! d) e)
10% MORE!
Now 132g! f)
15% BIGGER!
Now 184g!
Was: 50ml
Was: 120g
Was: 160g

15. 2) Find the original size of these items before the increase.
100%
50%
50% BIGGER!
Now 90g!
1) How big was the burger
before the increase?
Was: 60g 90
Answers
2) Find the original size of these items before the increase. a)
50% BIGGER!
Now 120g! b)
25% EXTRA!
Now 75g! c)
20% MORE!
Now 96ml!
Was: 80g
Was: 60g
Was: 80ml
20% EXTRA!
Now 60ml! d) e)
10% MORE!
Now 132g! f)
15% BIGGER!
Now 184g!
Was: 50ml
Was: 120g
Was: 160g

16. 2) Find the original size of these items before the increase.
100%
50%
50% BIGGER!
Now 75g!
1) How big was the burger
before the increase?
Was: 50g 75
2) Find the original size of these items before the increase. a)
50% BIGGER!
Now 135g! b)
25% EXTRA!
Now 150g! c)
20% MORE!
Now 336m!
Was: 90g
Was: 120g
Was: 280ml
20% EXTRA!
Now 54ml! d) e)
30% MORE!
Now 156g! f)
35% BIGGER!
Now 243g!
Was: 45ml
Was: 156g
Was: 180g

17. 2) Find the original size of these items before the increase.
100%
50%
50% BIGGER!
Now 75g!
1) How big was the burger
before the increase?
Was: 50g 75
Answers
2) Find the original size of these items before the increase. a)
50% BIGGER!
Now 135g! b)
25% EXTRA!
Now 150g! c)
20% MORE!
Now 336m!
Was: 90g
Was: 120g
Was: 280ml
20% EXTRA!
Now 54ml! d) e)
30% MORE!
Now 156g! f)
35% BIGGER!
Now 243g!
Was: 45ml
Was: 120g
Was: 180g

18. How much did the t-shirt cost
SALE!
50% OFF!
Now £15!
How much did the t-shirt cost
before the discount?
How much do you save?
50%
50%
50% 15 15
£15
100% = £30

19. How much did the t-shirt cost
SALE!
50% OFF!
Now £6!
How much did the t-shirt cost
before the discount?
How much do you save?
50%
50%
50% 6 6 £6
100% = £12

20. How much did the shoes cost
SALE!
25% OFF!
Now £60!
How much did the shoes cost
before the discount?
How much do you save?
75%
25%
25% 20 20
£60
100% = £80

21. How much did the hoodie cost
SALE!
25% OFF!
Now £21!
How much did the hoodie cost
before the discount?
How much do you save?
75%
25%
25% 7 7
£21
100% = £28

22. How much did the jeans cost
SALE!
20% OFF!
Now £28!
How much did the jeans cost
before the discount?
How much do you save?
80%
20%
20% 7 7
£28
100% = £35

23. How much did the hoodie cost
SALE!
20% OFF!
Now £20!
How much did the hoodie cost
before the discount?
How much do you save?
80%
20%
20% 5 5
£20
100% = £25

24. How much did the skirt cost
SALE!
10% OFF!
Now £54!
How much did the skirt cost
before the discount?
How much do you save?
10%
90%
10% 6 6
£54
100% = £60

25. How much did the shoes cost
SALE!
10% OFF!
Now £63!
How much did the shoes cost
before the discount?
How much do you save?
10%
90%
10% 7 7
£63
100% = £70

26. 2) Find the price of the clothes before the sale.
75%
25%
1) How much was the cap
before the discount?
25% OFF!
Now £30!
Was: £40
25%
2) Find the price of the clothes before the sale. a) b) c)
25% OFF!
Now £27!
20% OFF!
Now £40!
20% OFF!
Now £28!
Was: £36
Were: £50
Was: £35
10% OFF!
Now £54! d) e)
30% OFF!
Now £21! f)
35% OFF!
Now £52!
Were: £60
Was: £30
Was: £80

27. 2) Find the price of the clothes before the sale.
75%
25%
1) How much was the cap
before the discount?
25% OFF!
Now £30!
Was: £40
25%
Answers
2) Find the price of the clothes before the sale. a) b) c)
25% OFF!
Now £27!
20% OFF!
Now £40!
20% OFF!
Now £28!
Was: £36
Were: £50
Was: £35
10% OFF!
Now £54! d) e)
30% OFF!
Now £21! f)
35% OFF!
Now £52!
Were: £60
Was: £30
Was: £80

28. 1) How much were the socks before the discount?
75%
25%
1) How much were the socks
before the discount?
25% OFF!
Now £6!
Were: £8 £6
2) Find the price of the clothes before the sale. a) b) c)
25% OFF!
Now £24!
20% OFF!
Now £36!
20% OFF!
Now £52!
Was: £32
Was: £45
Was: £65
10% OFF!
Now £13.50! d) e)
60% OFF!
Now £48! f)
45% OFF!
Now £27.50!
Was: £15
Were: £120
Was: £50

29. Answers 75% 25% 1) How much were the socks before the discount?
25% OFF!
Now £6!
Were: £8 £6
Answers
2) Find the price of the clothes before the sale. a) b) c)
25% OFF!
Now £24!
20% OFF!
Now £36!
20% OFF!
Now £52!
Was: £32
Was: £45
Was: £65
10% OFF!
Now £13.50! d) e)
60% OFF!
Now £48! f)
45% OFF!
Now £27.50!
Was: £15
Were: £120
Was: £50

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