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Add 72/20 and 15/21

1st number: 3 12/20, 2nd number: 15/21

72/20 + 15/21 is 151/35.

Steps for adding fractions

  1. Find the least common denominator or LCM of the two denominators:
    LCM of 20 and 21 is 420

    Next, find the equivalent fraction of both fractional numbers with denominator 420
  2. For the 1st fraction, since 20 × 21 = 420,
    72/20 = 72 × 21/20 × 21 = 1512/420
  3. Likewise, for the 2nd fraction, since 21 × 20 = 420,
    15/21 = 15 × 20/21 × 20 = 300/420
  4. Add the two like fractions:
    1512/420 + 300/420 = 1512 + 300/420 = 1812/420
  5. 1812/420 simplified gives 151/35
  6. So, 72/20 + 15/21 = 151/35
    In mixed form: 411/35

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