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The number that rotates when multiplied

numberscyclic-numbersfractionsdigits

Look at 142857. Multiply it by 2: 285714. By 3: 428571. By 4: 571428. By 5: 714285. By 6: 857142. Every result is the same six digits cycled around.

  1. What is 142857 × 7?
  2. Why does this happen? Where does the number come from?
  3. Name another number with the same property.
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Work out 1/7 as a decimal.

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