Question

45 632 = 4 x 10 000 + 5 x __________ + 6 x __________ + 3 x _______ + 2 x 1=?

Answer 1

45,632 = 4 × 10,000 + 5 × 1,000 + 6 × 100 + 3 × 10 + 2 × 1

450,302 = 4 × 100,000 + 5 × 10,000 + 3 × 100 + 2 × 1

8,307,050 = 8 × 1,000,000 + 3 × 100,000 + 7 × 1,000 + 5 × 10

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• Decide which is the last digit to keep

• Leave it the same if the next digit is less than 5 (this is called rounding down)

• Increase it by 1 if the next digit is 5 or more (this is called rounding up)

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1156

nearest 10: 1156 ≈ 1160   (6 ≥ 5)

nearest 100: 1156 ≈ 1200 (5 ≥ 5)

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1,420,000 m²

nearest 100,000: 1,420,000 ≈ 1,400,000    (2 < 5)