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Add 21/28 and 9/15

21/28 + 9/15 is 27/20.

Steps for adding fractions

  1. Find the least common denominator or LCM of the two denominators:
    LCM of 28 and 15 is 420

    Next, find the equivalent fraction of both fractional numbers with denominator 420
  2. For the 1st fraction, since 28 × 15 = 420,
    21/28 = 21 × 15/28 × 15 = 315/420
  3. Likewise, for the 2nd fraction, since 15 × 28 = 420,
    9/15 = 9 × 28/15 × 28 = 252/420
  4. Add the two like fractions:
    315/420 + 252/420 = 315 + 252/420 = 567/420
  5. 567/420 simplified gives 27/20
  6. So, 21/28 + 9/15 = 27/20
    In mixed form: 17/20

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