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Add 20/15 and 7/21

1st number: 1 5/15, 2nd number: 7/21

20/15 + 7/21 is 5/3.

Steps for adding fractions

  1. Find the least common denominator or LCM of the two denominators:
    LCM of 15 and 21 is 105

    Next, find the equivalent fraction of both fractional numbers with denominator 105
  2. For the 1st fraction, since 15 × 7 = 105,
    20/15 = 20 × 7/15 × 7 = 140/105
  3. Likewise, for the 2nd fraction, since 21 × 5 = 105,
    7/21 = 7 × 5/21 × 5 = 35/105
  4. Add the two like fractions:
    140/105 + 35/105 = 140 + 35/105 = 175/105
  5. 175/105 simplified gives 5/3
  6. So, 20/15 + 7/21 = 5/3
    In mixed form: 12/3

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