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Grade 5

The decimal point takes a walk

Shift the decimal point and a number changes by a surprising amount -- the trick is counting the nines hiding in the difference.

  1. 1

    One step to the left

    Move the decimal point of a number one place to the left. The number is now 18.07218.072 smaller than it was. What is the number?
  2. 2

    One step to the right

    Move the decimal point of a number one place to the right. The number is now 175.05175.05 larger than it was. What is the number?
  3. 3

    Two steps to the left

    Move the decimal point of a number two places to the left. The number is now 198.891198.891 smaller than it was. What is the number?