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Add 15/5 and 18/21

1st number: 3 0/5, 2nd number: 18/21

15/5 + 18/21 is 27/7.

Steps for adding fractions

  1. Find the least common denominator or LCM of the two denominators:
    LCM of 5 and 21 is 105

    Next, find the equivalent fraction of both fractional numbers with denominator 105
  2. For the 1st fraction, since 5 × 21 = 105,
    15/5 = 15 × 21/5 × 21 = 315/105
  3. Likewise, for the 2nd fraction, since 21 × 5 = 105,
    18/21 = 18 × 5/21 × 5 = 90/105
  4. Add the two like fractions:
    315/105 + 90/105 = 315 + 90/105 = 405/105
  5. 405/105 simplified gives 27/7
  6. So, 15/5 + 18/21 = 27/7
    In mixed form: 36/7

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