Wednesday, October 10, 2012

Multiplying a 2-digit number by 29

Follow the Following Steps:
  1. Multiply by 3.
  2. Add one zero.
  3. From this, subtract the original number.

   Example:1

  1. The 2-digit number chosen to multiply by 29 is 21.
  2. Multiply by 3: 3 × 21 = 63
  3. Add one zero: 630
  4. Subtract original number:
    630 - 21 = 610 - 1 = 609
  5. So 21 × 29 = 609.
   Example:2
  1. The 2-digit number chosen to multiply by 29 is 81.
  2. Multiply by 3: 3 × 81 = 243
  3. Add one zero: 2430
  4. Subtract the original number:
    2430 - 81 = 2350 - 1 = 2349
  5. So 81 × 29 = 2349.

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