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Dividing A 2- Or 3-digit Number By 25

Dividing A 2- Or 3-digit Number By 25

Dividing a 2- or 3-digit number by 25

  1. Select a 2-digit number. (Choose larger numbers when you feel sure about the method.)
  2. Multiply by 4 (or by 2 twice).
  3. Move the decimal point two places to the left.
   Example:
  1. The 2-digit number chosen to divide by 25 is 38.
  2. Multiply by 4: 4 × 38 = 4 × 30 = 120 + 32 = 152.
  3. Move the decimal point 2 places to the left: 1.52
  4. So 38 divided by 25 = 1.52.

   See the pattern?

  1. The 3-digit number chosen to divide by 25 is 641.
  2. Multiply by 2 twice:
    2 × 64 = 1282.
    2 × 1282 = 2400 + 164 = 2564.
  3. Move the decimal point 2 places to the left: 25.64.
  4. So 641 divided by 25 = 25.64.

Practice multiplying left to right or by 2 twice and you will be able to do these computations quickly and accurately.





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26 Jul, 2021, 18:43:42 PM