Addition and Subtraction Adding money using column addition
Addition and Subtraction Adding money using column addition Objectives Day 1 Add amounts of money using expanded and compact addition. Day 2 Add amounts of money using expanded and compact addition. © hamilton-trust. org. uk 1 Year 4
Addition and Subtraction Adding money using column addition Starters Day 1 Add any pair of 2 -digit numbers (pre-requisite skills) Day 2 Use place value to add and subtract (pre-requisite skills) © hamilton-trust. org. uk 2 Year 4
Addition and Subtraction Adding money using column addition Starter Day 1 Add any pair of 2 -digit numbers © hamilton-trust. org. uk 3 Year 4
Addition and Subtraction Adding money using column addition Starter Use place value to add and subtract © hamilton-trust. org. uk 4 Year 4
Addition and Subtraction Adding money using column addition Objectives Day 1 Add amounts of money using expanded and compact addition. © hamilton-trust. org. uk 5 Year 4
Day 1: Add amounts of money using expanded and compact addition. We can use expanded addition to add £ 3. 24 and £ 2. 58. Partition the amounts into £s, 10 ps and 1 ps. Line the columns up neatly and don’t forget a blank ‘waiting line’ under the second number. £ 3 20 p 4 p + £ 2 50 p 8 p 10 p £ 5 80 p 2 p £ 5 + 80 p + 2 p = £ 5. 82 Next add the 10 ps. 20 p + 50 p + 10 p = ? Add the 1 ps. 4 p + 8 p = 12 p. We put 10 p under the 10 ps in the waiting line and 2 p under the 1 ps in the answer line. Then the £s. £ 3 + £ 2 = ? Finally recombine the pounds and pence. © hamilton-trust. org. uk 6 Year 4
Day 1: Add amounts of money using expanded and compact addition. 324 + 258 1 Try adding 324 and 258 using compact addition. 582 Let’s check through that. . . 1 s £ 3. 24 + £ 2. 58 1 10 s 100 s £ 5. 82 We can add £ 3. 24 and £ 2. 58 in the same way, without partitioning the amounts…! © hamilton-trust. org. uk 7 Year 4
Day 1: Add amounts of money using expanded and compact addition. Work in pairs, one to use expanded addition and the other to use compact addition to work out £ 4. 26 + £ 2. 37. Did you get the same answer? Let’s check through… £ 4 20 p 6 p + £ 2 30 p 7 p 10 p £ 4. 26 + £ 2. 37 1 £ 6 60 p 3 p £ 6. 63 £ 6 + 60 p + 3 p = £ 6. 63 Who can talk us through the compact addition? Who can talk us through the expanded addition? © hamilton-trust. org. uk 8 Year 4
Day 1: Add amounts of money using expanded and compact addition. Did you get the same answer? Now swap roles to work out £ 5. 45 + £ 3. 25. Let’s check through… £ 5 40 p 5 p + £ 3 20 p 5 p 10 p £ 5. 45 + £ 3. 25 1 £ 8 70 p 0 p £ 8. 70 £ 8 + 70 p + 0 p = £ 8. 70 Who can talk us through the compact addition? Who can talk us through the expanded addition? © hamilton-trust. org. uk 9 Year 4
Day 1: Add amounts of money using expanded and compact addition. Now find the exact total and compare with your approximation. You can choose which way to do it… £ 4. 17 + £ 2. 76. What is the approximate total? What would each amount be to the nearest pound? Let’s check through. . . £ 4 10 p 7 p + £ 2 70 p 6 p 10 p £ 4. 17 + £ 2. 76 1 £ 6 90 p 3 p £ 6. 93 £ 6 + 90 p + 3 p = £ 6. 93 Who can talk us through the compact addition? Who can talk us through the expanded addition? © hamilton-trust. org. uk 10 Year 4
Challenge © hamilton-trust. org. uk 11 Year 4
Addition and Subtraction Adding money using column addition Objectives Day 2 Add amounts of money using expanded and compact addition. © hamilton-trust. org. uk 12 Year 4
Day 2: Add amounts of money using expanded and compact addition. Work out 374 + 283 using compact addition. Let’s check through… What happened when we added 70 and 80? We can add £ 3. 74 and £ 2. 83 in the same way. 374 + 283 1 £ 3. 74 + £ 2. 83 1 657 £ 6. 57 The 70 p and 80 p make £ 1. 50. 5 goes under the 10 ps and the £ 1 under the pounds. © hamilton-trust. org. uk 13 Year 4
Day 2: Add amounts of money using expanded and compact addition. £ 3. 7 8 + £ 2. 4 5 11 Now try £ 3. 78 + £ 2. 45 using compact addition. £ 6. 2 3 Let’s check through. . . We had an extra 10 p and an extra £ 1 in this one. © hamilton-trust. org. uk 14 Year 4
Day 2: Add amounts of money using expanded and compact addition. Work out £ 4. 62 + £ 2. 75. You can use compact addition or the expanded method if you prefer. Let’s check through. . . £ 4 60 p 2 p + £ 2 70 p 5 p £ 1 £ 4. 62 + £ 2. 75 1 £ 7 30 p 7 p £ 7. 37 £ 7 + 30 p + 7 p = £ 7. 37 Who can talk us through the compact addition? Who can talk us through the expanded addition? © hamilton-trust. org. uk 15 Year 4
Day 2: Add amounts of money using expanded and compact addition. Work out £ 5. 58 + £ 5. 75. You can use compact addition or the expanded method if you prefer. Let’s check through… £ 5 50 p 8 p + £ 5 70 p 5 p £ 1 10 p £ 5. 58 + £ 5. 75 11 £ 11 30 p 3 p £ 11. 33 £ 11 + 30 p + 3 p = £ 11. 33 Who can talk us through the compact addition? Who can talk us through the expanded addition? © hamilton-trust. org. uk 16 Year 4
Investigation: Adult Sheet © hamilton-trust. org. uk 17 Year 1
Investigation: Child Sheet © hamilton-trust. org. uk 18 Year 1
Challenge © hamilton-trust. org. uk 19 Year 4
Addition and Subtraction Adding money using column addition Well Done! You’ve completed this unit. Objectives Day 1 Add amounts of money using expanded and compact addition. Day 2 Add amounts of money using expanded and compact addition. © hamilton-trust. org. uk 20 Year 4
Problem solving and reasoning questions Complete these additions using expanded column addition. (i) £ 5. 78 + £ 4. 22 (iii) £ 3. 17 + £ 6. 83 (ii) £ 2. 56 + £ 7. 44 Did you notice a pattern? Can you write two more additions like this? Is a column addition calculation the most efficient way to find: £ 4. 99 + £ 7. 46 £ 8. 06 + £ 8. 06 £ 4. 31 + £ 5. 69? Write the missing numbers in this calculation: £ 10 p 1 p 4 + 5 7 6 ______ 4 5 If £ 3. 47 is subtracted from a number to leave £ 3. 85, what was the number? © hamilton-trust. org. uk 21 Year 4
Problem solving and reasoning questions answers Complete these additions using expanded column addition. (i) £ 5. 78 + £ 4. 22 = £ 10 (ii) £ 2. 56 + £ 7. 44 = £ 10 (iii) £ 3. 17 + £ 6. 83 = £ 10 £ 8. 06 + £ 8. 06 = £ 16. 12. Double each of the £s and ps. £ 4. 31 + £ 5. 69 = £ 10. 31 and 69 are complements to 100, add that (as £ 1) to £ 4 and £ 5. Errors with column subtraction may be due to unclear setting out, missing the numbers moved over into adjacent columns or simply arithmetical. For examples of setting out expanded column addition, see the teaching for the Unit or the corresponding Power. Point. Did you notice a pattern? All three additions total £ 10. Can you write two more additions like this? Check children’s examples. Can they articulate that the 1 ps column always adds to 10 p, the 10 ps add to 90 p and the £ 1 s add to £ 9 (before moving amounts across columns)? Write the missing numbers in this calculation: £ 10 p 1 p 4 7 7 + 5 6 8 1______ 10 4 5 Note the 1 s in the waiting line. If £ 3. 47 is subtracted from a number to leave £ 3. 85, what was the number? £ 7. 32. Watch for children who have subtracted £ 3. 47 from £ 3. 85 (38 p) – a bar model can help clarify that the answer is found by adding the 2 amounts: Is a column addition calculation the most efficient way to find: £ 4. 99 + £ 7. 46 = £ 12. 45. Add £ 5 to £ 7. 46 and subtract 1 p. © hamilton-trust. org. uk 22 Year 4
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