BajrangAssociate
Back to mental maths

Multiply by 11

Add neighbouring digits to multiply any number by 11 instantly

The Rule

  1. 1Write an imaginary 0 on either side of the number.
  2. 2Add each pair of neighbouring digits, moving from right to left.
  3. 3If any sum is 10 or more, write down the last digit and carry 1 into the next sum on the left.
  4. 4The resulting digits, read left to right, are the answer.