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  1. DECIMALS Contents Division Multiplication

  2. The grid method formultiplyingwholenumbers

  3. The grid method formultiplying decimals

  4. Using the standard column method What is 2.28 × 7? Start by finding an approximate answer: 2.28 × 7  2 × 7 = 14 2.28 × 7 is equivalent to 228 × 7 ÷ 100 228 Answer × 7 15 9 6 2.28 × 7 = 1596 ÷ 100 = 15.96 1 5

  5. Using the standard column method What is 392.7 × 0.8? Again, start by finding an approximate answer: 392.7 × 0.8  400 × 1 = 400 392.7 × 0.8 is equivalent to 3927 × 8 ÷ 100 3927 Answer × 8 392.7 × 0.8 = 31416 ÷ 10 ÷ 10 31 4 1 6 = 314.16 7 2 5

  6. Drag and drop multiplication problem

  7. Multiplying two-digit numbers Calculate 57.4 × 24. Estimate: 60 × 25 = 1500 Equivalent calculation: 57.4 × 10 × 24 ÷ 10 = 574 × 24 ÷ 10 574 × 24 4 × 574 = 2296 20 × 574 = 11480 13776 Answer: 13776 ÷ 10 = 1377.6

  8. Multiplying two-digit numbers Calculate 23.2 × 1.8. Estimate: 23 × 2 = 46 Equivalent calculation: 23.2 × 10 × 1.8 × 10 ÷ 100 = 232 × 18 ÷ 100 232 × 18 8 × 232 = 1856 10 × 232 = 2320 4176 Answer: 4176 ÷ 100 = 41.76

  9. Multiplying two-digit numbers Calculate 394 × 0.47. Estimate: 400 × 0.5 = 200 Equivalent calculation: 394 × 0.47 × 100 ÷ 100 = 394 × 47 ÷ 100 394 × 47 7 × 394 = 2758 40 × 394 = 15760 18518 Answer: 18518 ÷ 100 = 185.18

  10. DECIMALS Contents • A1 Division

  11. Dividing decimals – Example 1 Dividend Divisor What is 259.2 ÷ 6?

  12. Using repeated subtraction 6 259.2 - 240.0 - 18.0 - 1.2 Start by finding an approximate answer: 259.2 ÷ 6 240 ÷ 6 = 40 6 ×40 19.2 6 ×3 1.2 6 ×0.2 0 Answer: 43.2

  13. Using short division Start by finding an approximate answer: 240 ÷ 6 = 40 259.2 ÷ 6 0 4 3 . 2 6 2 5 9 . 2 2 1 1 2.59 ÷ 6 = 43.2

  14. Dividing decimals – Example 2 Dividend Divisor What is 714.06 ÷ 9?

  15. Using repeated subtraction 9 714.06 - 630.00 - 81.00 - 2.70 - 0.36 Start by finding an approximate answer: 714.06 ÷ 9 720 ÷ 9 = 80 9 ×70 84.06 9 ×9 3.06 9 ×0.3 0.36 9 ×0.04 0 Answer: 79.34

  16. Using short division 9 7 1 4 . 0 6 Start by finding an approximate answer: 714.06 ÷ 9 720 ÷ 9 = 80 0 7 9 . 3 4 7 8 3 3 714.06 ÷ 9 = 79.34

  17. Drag and drop division problem