Multiply by 11

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Multiplying numbers by 11
Quick multiplication trick
2by2 Multiplication

Multiplying any number by 11 is a simple two-step process:

  1. Add the first and second digits together. For example, for 13×11, calculate:
    1 + 3 = 4
  2. Place the result 4 between the original digits. Therefore:
    13 × 11 = 1[1+3]3 = 143 = 143

With this quick trick, multiplying any number by 11 becomes effortless!

Practice now
  • 12×11 = 1[1+2]2 = 1[3]2 = 132
  • 15×11 = 1[1+5]5 = 1[6]5 = 165
  • 32×11 = 3[3+2]2 = 3[5]2 = 352
  • 27×11 = 2[2+7]7 = 2[9]7 = 297
  • 81×11 = 8[8+1]1 = 8[9]1 = 891
  • 38×11 = 3[3+8]8 = 3[11]8 = 4[1]8 = 418
    Note: 1 carried over.
  • 67×11 = 6[6+7]7 = 6[13]7 = 7[3]7 = 737
    Note: 1 carried over.