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Add 21/12 and 20/7

1st number: 1 9/12, 2nd number: 2 6/7

21/12 + 20/7 is 129/28.

Steps for adding fractions

  1. Find the least common denominator or LCM of the two denominators:
    LCM of 12 and 7 is 84

    Next, find the equivalent fraction of both fractional numbers with denominator 84
  2. For the 1st fraction, since 12 × 7 = 84,
    21/12 = 21 × 7/12 × 7 = 147/84
  3. Likewise, for the 2nd fraction, since 7 × 12 = 84,
    20/7 = 20 × 12/7 × 12 = 240/84
  4. Add the two like fractions:
    147/84 + 240/84 = 147 + 240/84 = 387/84
  5. 387/84 simplified gives 129/28
  6. So, 21/12 + 20/7 = 129/28
    In mixed form: 417/28

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