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Multiplying A 2-digit Number By 4 3/7

Multiplying A 2-digit Number By 4 3/7

Multiplying a 2-digit number by 4 3/7

  1. Multiply the number by 3.
  2. Add one zero.
  3. Add the original number.
  4. Divide by 7.

 

   Example:
  1. If the 2-digit number chosen to multiply by 4 3/7 is 21:
  2. Multiply by 3: 3 × 21 = 63
  3. Add one zero: 630
  4. Add the original number. 630 + 21 = 651
  5. Divide by 7: 651/7 = 93
  6. So 4 3/7 × 21 = 93.

   See the pattern?

  1. If the number to be multiplied by 4 3/7 is 62:
  2. Multiply by 3: 3 × 62 = 186
  3. Add one zero: 1860
  4. Add the original number. 1860 + 62 = 1860 + 60 + 2 = 1920 + 2 = 1922
  5. Divide by 7: 1922/7 = 274 4/7
  6. So 4 3/7 × 62 = 274 4/7.




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26 Sep, 2021, 03:08:16 AM