Åk 6–9

 3.8 Exercises – Multiplication and Division

1. Write the following additions as products?

 Ex: 2 + 2 + 2 + 2 = 4 · 2 a) 4 + 4 + 4 + 4 + 4 + 4 b) 7 + 7 + 7 + 7 c) 2 + 2 + 2 + 2 + 2 + 2 + 2 + 2 d) 1 + 1 + 1 + 1 + 1 e) 9 + 9 + 9 + 9 + 9 + 9 + 9 f) 5 + 5 + 5 + 5 + 5 + 5 + 5 + 5 + 5 g) 12 + 12 + 12 + 12 + 12 + 12 2. Which divisions represent the following subtraction?

 Ex: 8 - 2 - 2 - 2 - 2 = 0 8 ÷ 2 a) 20 - 5 - 5 - 5 - 5 = 0 b) 48 - 12 - 12 - 12 - 12 = 0 c) 72 - 18 - 18 - 18 - 18 = 0 d) 36 - 9 - 9 - 9 - 9 = 0 e) 120 - 24 - 24 - 24 - 24 - 24 = 0 f) 81 - 27 - 27 - 27 = 0 g) 44 - 11 - 11 - 11 - 11 = 0 3. Calculate according to the examples below.

 Ex: 58 · 7 (50 · 7) + (8 · 7) = 350 + 56 = 406 a) 96 ÷ 3 b) 27 · 5 c) 84 · 6 d) 62 ÷ 2 e) 936 ÷ 3 f) 385 · 9 g) 437 · 6 4. Calculate by using approximation.

 Ex: 26 · 37 ≈ 30 · 30 = 900 a) 74 · 28 ≈ b) 75 ÷ 9 ≈ c) 39 · 23 ≈ d) 57 ÷ 26 ≈ e) 83 ÷ 41 ≈ f) 87 ÷ 28 ≈ g) 27 · 94 ≈ 5. Calculate by using approximation.

 Ex: 110 · 58 ≈ 100 · 60 = 6,000 a) 814 · 69 ≈ b) 565 ÷ 18 ≈ c) 452 · 78 ≈ d) 656 ÷ 67 ≈ e) 18,431 ÷ 358 ≈ f) 87,825 ÷ 289 ≈ g) 591 · 712 ≈