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2011 Math Kangaroo

Problem 11

Problem 11 · 2011 Math Kangaroo Medium
Arithmetic & Operations place-value

Work out 2011 × 2.011201.1 × 20.11.

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Answer: C — 1
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Hint 1 of 2
Look at how the decimal points shift — the products may be the same.
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Hint 2 of 2
Compare 2011×2.011 with 201.1×20.11 by tracking the decimal places.
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Approach: spot that numerator and denominator are equal
  1. Numerator 2011×2.011 = 4044.121.
  2. Denominator 201.1×20.11 = 4044.121.
  3. They are equal, so the fraction is 1.
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