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Add 81/21 and 21/7

1st number: 3 18/21, 2nd number: 3 0/7

81/21 + 21/7 is 48/7.

Steps for adding fractions

  1. Find the least common denominator or LCM of the two denominators:
    LCM of 21 and 7 is 21

    Next, find the equivalent fraction of both fractional numbers with denominator 21
  2. For the 1st fraction, since 21 × 1 = 21,
    81/21 = 81 × 1/21 × 1 = 81/21
  3. Likewise, for the 2nd fraction, since 7 × 3 = 21,
    21/7 = 21 × 3/7 × 3 = 63/21
  4. Add the two like fractions:
    81/21 + 63/21 = 81 + 63/21 = 144/21
  5. 144/21 simplified gives 48/7
  6. So, 81/21 + 21/7 = 48/7
    In mixed form: 66/7

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