# 25022021 Find a percentage of an amount MATHSWATCH

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25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 L. O. To be able to § Find a percentage of an amount without a calculator § Use a multiplier to find a percentage of an amount Key Words percentage, multiplier, calculate Starter:

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 CONTENTS – Click to go to… NON CALCULATOR METHODS CALCULATOR

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 NON-CALCULATOR METHODS

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 The KEY PLAYERS in working out percentages! To find 10% Divide by 10 To find 1% Divide by 100 To find 25% Divide by 4 To find 50% Divide by 2 If you can work out these, you can work out ANY percentage!

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 We can use percentages that we know to find other percentages. Suggest ways to work out: 20% 2% 11% 15% 30% 60% 49% 75% 0. 5 % 150% 17. 5%

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Two lots of 10 % 5% Half of 10 % 15 % 10 % plus 5 % 2. 5 % Half of 5 % ( Half 10 % and then half again ) 12. 5 % 10 % plus 2. 5 % 11 % 10 % plus 1 % 17. 5 % 10 % plus 5 % plus 2. 5 % 21 % Two lots of 10 % plus 1 % 5 % ( Half of 10 % ) plus 1 % 6% 17 % 10 % plus 5 % plus two lots of 1 % 31 % Three lots of 10 % plus 1 % 29 % Three lots of 10 % then subtract 1 % 20 %

25/02/2021 Find a percentage of an amount To find 10%, just divide by 10 What is 10% of £ 15 ? £ 15 Answer = £ 1. 50 MATHSWATCH CLIP 86, 87 GRADE 3

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 To find 10%, just divide by 10 What is 10% of £ 18. 20 ? £ 1820 Answer = £ 1. 82

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Find 10% of the quantities shown. Question 2 Question 3 £ 675 £ 67. 50 Question 6 £ 3500 £ 350 Question 7 425 mm 42. 5 mm Question 10 7450 km 745 km Question 11 Question 12 4560 kg 9. 7 g 83 cm £ 0. 40 456 kg 0. 97 g 8. 3 cm 4 p Question 1 £ 54 £ 5. 40 Question 5 73 m 7. 3 m Question 9 Question 4 £ 2. 70 27 p Question 8 8. 43 litres 0. 843 litres

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 All the items below are given a 10% discount. Find the discount in each case. 5 7 2 £ £ 27. 50 £ 99 £ 9. 90 0 4 3 £ 634 £ 5. 40 5 £ 3. 35 p p 0 2 2 p 0

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 1) 10% of £ 400 2) 10% of £ 650 3) 10% of £ 55 4) 10% of £ 1000 5) 10% of £ 6. 20 6) 10% of £ 12. 40 7) 10% of £ 0. 50 8) 10% of £ 0. 10 9) 10% of 2435 g 10) 10% of 4552 secs 11) 10% of 1. 437 litres 12) 10% of 0. 34 Km 13) 10% of 0. 04 cm 14) 10% of 34. 5 °C £ 40 £ 5. 50 62 p or £ 0. 62 5 p or £ 0. 05 243. 5 g 0. 1437 litres 0. 004 cm £ 65 £ 100 £ 1. 24 1 p or £ 0. 01 455. 2 secs 0. 034 Km 3. 45°C

25/02/2021 Find a percentage of an amount Examples What is 20% of £ 140 ? 10% of £ 140 = £ 14 So 20% of £ 140 = £ 28 What is 20% of £ 1. 20 ? 10% of £ 1. 20 = 12 p So 20% = 24 p MATHSWATCH CLIP 86, 87 GRADE 3

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Find 20% of the quantities shown. Question 2 Question 3 £ 640 £ 128 Question 6 £ 3800 £ 760 Question 7 345 mm 69 mm Question 10 1564 km 312. 8 km Question 11 Question 12 4500 kg 4. 7 g 83 cm £ 0. 40 900 kg 0. 94 g 16. 6 cm 8 p Question 1 £ 84 £ 16. 80 Question 5 96 m 19. 2 m Question 9 Question 4 £ 1. 40 28 p Question 8 8. 4 litres 1. 68 litres

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 All the items below are given a 20% discount. Find the discount in each case. 5 7 2 £ £ 55. 00 £ 99 £ 19. 80 0 4 3 £ 6 £ 1268 £ 54 £ 10. 80 5 £ 3. 70 p p 0 2 4 p 0

Find a percentage 25/02/2021 of an amount Sale 20% off everything MATHSWATCH CLIP 86, 87 GRADE 3 Tricycle £ 12. 00 Bucket and Jack in Box Spade £ 8. 00 £ 6. 20 What price do I now pay for: *The ball __________ *The jack in box_________ *The bucket and spade _____ *The tricycle__________ Ball £ 3. 50

25/02/2021 Find a percentage of an amount Sale 30% off everything Binoculars Football Boots £ 30. 00 £ 64 MATHSWATCH CLIP 86, 87 GRADE 3 Ball £ 12. 20 Helmet £ 28. 40 What price do I now pay for: *The ball __________ *The binoculars_________ *The helmet_____ *The football boots __________

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Examples What is 5% of £ 80 ? 10% of £ 80 = £ 8 What is 15% of £ 80 ? 10% of £ 80 = £ 8 So 5% of £ 80 = £ 4 15% = 8 + 4 = £ 12 What is 5% of 40 p ? 10% of 40 p = 4 p What is 15% of £ 2. 40 ? 10% of £ 2. 40 = £ 0. 24 or 24 p So 5% = 2 p 5% = £ 0. 12 or 12 p 15% = 24 + 12 = 36 p

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Find 15% of the quantities shown. Question 2 Question 3 £ 680 £ 102 Question 6 £ 3600 £ 540 Question 7 428 mm 64. 2 mm Question 10 4460 km 669 km Question 11 Question 12 4500 kg 4. 4 g 83 cm £ 0. 40 675 kg 0. 66 g 12. 45 cm 6 p Question 1 £ 64 £ 9. 60 Question 5 86 m 12. 9 m Question 9 Question 4 £ 2. 80 42 p Question 8 8. 4 litres 1. 26 litres

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 All the items below are given a 15% discount. Find the discount in each case. 0 0 3 £ £ 45 £ 99 £ 14. 85 0 4 3 £ 6 £ 951 0 6. £ 3 54 p p £ 54 20 £ 8. 10 3 p

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Find 25% of the quantities shown. Question 1 £ 84 £ 21 Question 5 96 m 24 m Question 9 4500 kg 1125 kg Question 2 Question 3 £ 320 £ 80 Question 6 £ 3600 £ 900 Question 7 248 mm 62 mm Question 10 1564 km 391 km Question 11 Question 12 4. 28 g 68 cm £ 0. 40 1. 07 g 17 cm 10 p Question 4 £ 1. 80 45 p Question 8 8. 4 litres 2. 1 litres

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 All the items below are given a 25% discount. Find the discount in each case. 0 6 3 £ £ 90 4 0 1 £ £ 26 0 4 8 £ 6 0 6. £ 4 £ 1710 £ 1. 15 £ 54 20 £ 13. 50 5 p p

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Calculate the percentages of the quantities shown. Question 1 40% of £ 24 £ 9. 60 Question 5 Question 2 60% £ 250 £ 150 Question 6 Question 3 70% of£ 3000 £ 2100 Question 7 Question 4 80% of £ 1. 90 1. 52 p Question 8 90% of 45 mm 75% of 240 km 40. 5 mm Question 10 180 km Question 11 Question 12 70% of 450 kg 30% of 8. 1 g 40% 83 cm 60% of £ 0. 40 315 kg 2. 43 g 33. 2 cm 24 p 50 % of 96 m 48 m Question 9 40% of 4. 4 l 1. 76 litres

Find 10% of the following 1. £ 54 2. £ 675 3. £ 3500 4. £ 2. 70 5. 73 m 6. 425 mm 7. 7450 km 8. 8. 43 litres 9. 4560 kg 10. 9. 7 g 11. 83 cm 12. £ 0. 40 Find 15% of the following 1. £ 64 2. £ 680 3. £ 3600 4. £ 2. 80 5. 86 m 6. 428 mm 7. 4460 km 8. 8. 4 litres 9. 4500 kg 10. 4. 4 g 11. 83 cm 12. £ 0. 40

Find 20% of the following 1. £ 84 2. £ 640 3. £ 3800 4. £ 1. 40 5. 96 m 6. 345 mm 7. 1564 km 8. 8. 4 litres 9. 450 kg 10. 4. 7 g 11. 83 cm 12. £ 0. 40 Find 25% of the following 1. £ 84 2. £ 320 3. £ 3600 4. £ 1. 80 5. 96 m 6. 248 mm 7. 1564 km 8. 8. 4 litres 9. 4500 kg 10. 4. 28 g 11. 68 cm 12. £ 0. 40

Find 30% of the following 1. £ 84 2. £ 430 3. £ 5700 4. £ 1. 90 5. 96 m 6. 360 mm 7. 1560 km 8. 4. 4 litres 9. 4500 kg 10. 8. 1 g 11. 83 cm 12. £ 0. 40 Mixed percentage Questions 1. 40% of £ 24 2. 60% of £ 250 3. 70% of £ 3000 4. 80% of £ 1. 90 5. 50% of 96 m 6. 90% of 45 mm 7. 75% of 240 km 8. 40% of 4. 4 litres 9. 70% of 450 kg 10. 30% of 8. 1 g 11. 40% of 83 cm 12. 60% of £ 0. 40

2/25/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Finding percentages treasure hunts! There are three treasure hunts around the room Finding 10% or 20% – GREEN cards Finding 5%, 10%, 15%– ORANGE cards Finding multiples of 5%– RED cards § Choose your level of challenge and complete the treasure hunt of your choice § Remember I need to see WORKING and you are only finished if you come to me with the correct ORDER OF CARDS!

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Percentages trail Find the 10 hidden questions around the room and answer them on your student sheet. You choose whether you answer green, amber or red depending on how confident you feel about them. You can answer them in any order you want.

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Solutions Green 1. £ 27 2. £ 3. 20 3. £ 3. 50 4. £ 1. 20 5. £ 4. 50 6. £ 48 7. £ 2. 80 8. £ 41 9. £ 0. 43 10. £ 244. 50 Amber 1. £ 10. 80 2. £ 19. 20 3. £ 5. 60 4. £ 108 5. £ 1. 80 6. £ 19. 20 7. £ 22. 40 8. £ 24. 60 9. £ 12. 90 10. £ 228. 20 Red 1. £ 5. 94 2. £ 14. 40 3. £ 13. 72 4. £ 103. 20 5. £ 1. 26 6. 83. 52 7. £ 4. 90 8. £ 50. 84 9. £ 29. 67 10. £ 22. 82

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Percentage “go and find” Get into teams. You can only have 4 or 5 in a team. Each time a question is answered, you need to pick one person from your team to go and find the answer. When you have the answer, come back to you table and sit back down. The team with the most at the end of the challenge will be the winners….

Find a percentage of an amount 25/02/2021 GO AND FIND! What is 10% of 17? 1. 7 MATHSWATCH CLIP 86, 87 GRADE 3

Find a percentage of an amount 25/02/2021 GO AND FIND! What is 10% of 60? 6 MATHSWATCH CLIP 86, 87 GRADE 3

Find a percentage of an amount 25/02/2021 GO AND FIND! What is 50% of 18? 9 MATHSWATCH CLIP 86, 87 GRADE 3

Find a percentage of an amount 25/02/2021 MATHSWATCH CLIP 86, 87 GRADE 3 GO AND FIND! What is 10% of 510? 51

Find a percentage of an amount 25/02/2021 GO AND FIND! What is 50% of 20? 10 MATHSWATCH CLIP 86, 87 GRADE 3

25/02/2021 Find a percentage of an amount GO AND FIND! What is 1% of 87? 0. 87 MATHSWATCH CLIP 86, 87 GRADE 3

Find a percentage of an amount 25/02/2021 GO AND FIND! What is 50% of 84? 42 MATHSWATCH CLIP 86, 87 GRADE 3

Find a percentage of an amount 25/02/2021 MATHSWATCH CLIP 86, 87 GRADE 3 GO AND FIND! What is 10% of 540? 54

Find a percentage of an amount 25/02/2021 MATHSWATCH CLIP 86, 87 GRADE 3 GO AND FIND! What is 10% of 690? 69

Find a percentage of an amount 25/02/2021 MATHSWATCH CLIP 86, 87 GRADE 3 GO AND FIND! What is 50% of 294? 147

Find a percentage of an amount 25/02/2021 MATHSWATCH CLIP 86, 87 GRADE 3 GO AND FIND! What is 10% of 880? 88

Find a percentage of an amount 25/02/2021 GO AND FIND! What is 1% of 820? 8. 2 MATHSWATCH CLIP 86, 87 GRADE 3

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 1. Find 10% of the following amounts a) 20 b) 30 c) 280 d) 320 e) 42 f) 68 g) 72 h) 94 2. Find 20% of the following amounts a) 40 b) 100 c) 80 d) 120 e) 60 f) 70 g) £ 1. 50 h) £ 2. 80 3. Find 30% of the following amounts a) 40 b) 100 c) 80 d) 120 e) 60 f) 70 g) £ 1. 50 h) £ 2. 80

Find a percentage of an amount 25/02/2021 MATHSWATCH CLIP 86, 87 GRADE 3 Copy the table and fill in… 8 10% of 80 15 10% of 150 10% of 120 20% of 60 30% of 40 30% of 50 12 20% of 75 40% of 20 20% of 40

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Spot the errors… most spotted gets a prize! Work out 35% of £ 120 10% = £ 1. 20 30% = £ 3. 60 5% = 60 35% = £ 1. 20 + £ 3. 60 + 60 = £ 64. 80

25/02/2021 Find a percentage of an amount To find 1%, just divide by 100 What is 1% of £ 200 ? £ 200 Answer = £ 2 MATHSWATCH CLIP 86, 87 GRADE 3

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 1) 1% of £ 300 2) 1% of £ 450 3) 1% of £ 25 4) 1% of £ 14 5) 1% of £ 6500 6) 1% of £ 100 7) 1% of £ 75 8) 1% of £ 18 9) 1% of £ 1 10) 1% of £ 810 11) 1% of 24 g 12) 1% of 3453 secs 13) 1% of 18. 35 Km 14) 1% of 0. 3 litres £ 3 25 p or £ 0. 25 £ 65 75 p or £ 0. 75 1 p or £ 0. 01 0. 24 g 0. 1835 Km £ 4. 50 14 p or £ 0. 14 £ 1 18 p or £ 0. 18 £ 8. 10 34. 53 secs 0. 003 litres

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Examples What is 11% of £ 420 ? What is 11% of £ 2000 ? 10% of £ 420 = £ 42 10% of £ 2000 = £ 200 1% of £ 420 = £ 4. 20 1% of £ 2000 = £ 20 So 11% = 42 + 4. 20 So 11% = 200 + 20 = £ 46. 20 = £ 220

25/02/2021 Find a percentage of an amount 1) Find 10% of £ 30 2) Find 10% of £ 90 3) Find 10% of £ 200 4) Find 10% of £ 760 5) Find 10% of £ 68 6) Find 10% of £ 382 7) Find 1% of £ 500 8) Find 1% of £ 600 9) Find 1% of £ 70 10)Find 1% of £ 40 MATHSWATCH CLIP 86, 87 GRADE 3 1) 2) 3) 4) 5) 6) Find 20% of £ 50 Find 30% of £ 800 Find 60% of £ 320 Find 4% of £ 600 Find 8% of £ 1200 Find 7% of £ 900 1) 2) 3) 4) Find 15% of £ 460 Find 25% of £ 64 Find 22% of £ 700 Find 13% of £ 350

25/02/2021 Find a percentage of an amount £ 2 9 p or £ 0. 09 42 p or £ 0. 42 £ 120 1) 5% of £ 40 2) 5% of £ 1. 80 MATHSWATCH CLIP 86, 87 GRADE 3 63 p or £ 0. 63 3) 5% of £ 12. 60 68 p or £ 0. 68 4) 20% of £ 2. 10 5) 20% of £ 600 6) 20% of £ 3. 40 7) 15% of £ 140 8) 15% of £ 2. 40 9) 15% of 80 p 10) 2. 5% of £ 60 11) 2. 5% of £ 400 12) 2. 5% of 40 p 13) 12. 5% of £ 200 14) 12. 5% of £ 1. 60 15) 12. 5% of £ 4. 40 16) 17. 5% of £ 50 17) 17. 5% of 80 p 18) 17. 5% of £ 2000 19) 11% of £ 300 20) 6% of £ 24 21) 2% of £ 350 22) 12% of £ 180 23) 19% of £ 420 24) 16% of £ 5 25) ½% of £ 3000 26) 5. 5% of £ 200 27) 99% of £ 500 28) 39% of £ 800 29) 1. 5% of £ 100 30) ¼% of £ 6000 £ 21 £ 1. 50 £ 25 £ 8. 75 £ 33 £ 21. 60 £ 15 £ 312 36 p or £ 0. 36 £ 10 20 p or £ 0. 20 14 p or £ 0. 14 £ 1. 44 £ 79. 80 £ 11 £ 1. 50 12 p or £ 0. 12 1 p or £ 0. 01 55 p or £ 0. 55 £ 350 £ 7 80 p or £ 0. 80 £ 495 £ 15

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 CALCULATOR METHODS

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Using percentage multipliers § Convert the percentage to a decimal multiplier Ø To do this, just divide the percentage by 100 § Times the original amount by the multiplier

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 £ 2. 92 £ 25. 23 1) 22% of £ 13. 25 2) 38% of £ 66. 40 3) 8% of £ 11. 55 4) 64% of £ 240 5) 18% of £ 34. 99 6) 12. 5% of £ 19. 99 7) 20% of £ 2. 49 8) 33% of £ 67. 70 9) 41. 5% of £ 9. 99 10) 5. 5% of £ 17. 95 11) 17. 5% of £ 85. 55 12) 82% of 99 p 13) 45% of 25 p 14) 23. 5% of 89 p 15) 11% of 33 p 16) 3. 5% of 23 p 92 p or £ 0. 92 £ 6. 30 50 p or £ 0. 50 £ 4. 15 £ 14. 97 11 p 4 p or £ 0. 04 £ 153. 60 £ 2. 50 £ 22. 34 99 p or £ 0. 99 81 p or £ 0. 81 21 p or £ 0. 21 1 p or £ 0. 01

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 QUICK QUESTIONS! Answers on your mini whiteboards…

25/02/2021 Find a percentage of an amount 15 % of £ 1. 80 MATHSWATCH CLIP 86, 87 GRADE 3

2/25/2021 Find a percentage of an amount 22 % of £ 2000 MATHSWATCH CLIP 86, 87 GRADE 3

2/25/2021 Find a percentage of an amount 75 % of £ 200 MATHSWATCH CLIP 86, 87 GRADE 3

2/25/2021 Find a percentage of an amount 15 % of £ 500 MATHSWATCH CLIP 86, 87 GRADE 3

2/25/2021 Find a percentage of an amount 6 % of £ 50 MATHSWATCH CLIP 86, 87 GRADE 3

2/25/2021 Find a percentage of an amount 90 % of £ 30 MATHSWATCH CLIP 86, 87 GRADE 3

2/25/2021 Find a percentage of an amount 17. 5 % of £ 400 MATHSWATCH CLIP 86, 87 GRADE 3

2/25/2021 Find a percentage of an amount 12. 5 % of £ 4. 80 MATHSWATCH CLIP 86, 87 GRADE 3

2/25/2021 Find a percentage of an amount 17. 5 % of £ 8. 40 MATHSWATCH CLIP 86, 87 GRADE 3

2/25/2021 Find a percentage of an amount 16 % of £ 76 MATHSWATCH CLIP 86, 87 GRADE 3

25/02/2021 Find a percentage of an amount Q 1: Calculate 54% of £ 89 £ 48. 06 Q 3: Calculate 84% of 350 g 294 g Q 5: Calculate 71% of 28 l 19. 88 l Q 7: Calculate 7% of £ 750 £ 52. 50 MATHSWATCH CLIP 86, 87 GRADE 3 Q 2: Calculate 17% of 33 m 5. 61 m Q 4: Calculate 24% of \$450 \$108 Q 6: Calculate 43% of 16 kg 6. 88 kg Q 8: Calculate 39% of 7. 2 km 2. 808 km

25/02/2021 Find a percentage of an amount Q 1: Calculate 54% of £ 43 £ 23. 22 Q 3: Calculate 84% of 830 g 697. 2 g Q 5: Calculate 3% of 28 l 0. 84 l Q 7: Calculate 99% of £ 750 £ 742. 5 MATHSWATCH CLIP 86, 87 GRADE 3 Q 2: Calculate 17% of 85 m 14. 45 m Q 4: Calculate 24% of \$674 \$161. 76 Q 6: Calculate 9% of 16 kg 1. 44 kg Q 8: Calculate 63% of 7. 2 km 4. 536 km

25/02/2021 Find a percentage of an amount Q 1: Calculate 52% of £ 79 £ 41. 08 Q 3: Calculate 74% of 270 g 199. 8 g Q 5: Calculate 85% of 28 l 23. 8 l Q 7: Calculate 4% of £ 750 £ 30 MATHSWATCH CLIP 86, 87 GRADE 3 Q 2: Calculate 27% of 43 m 11. 61 m Q 4: Calculate 18% of \$490 \$88. 2 Q 6: Calculate 7% of 16 kg 1. 12 kg Q 8: Calculate 99% of 7. 2 km 7. 128 km

25/02/2021 Find a percentage of an amount MATHSWATCH CLIP 86, 87 GRADE 3 Challenge Try to do these WITH a multiplier, but WITHOUT a calculator…