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Add 21/7 and 15/8

1st number: 3 0/7, 2nd number: 1 7/8

21/7 + 15/8 is 39/8.

Steps for adding fractions

  1. Find the least common denominator or LCM of the two denominators:
    LCM of 7 and 8 is 56

    Next, find the equivalent fraction of both fractional numbers with denominator 56
  2. For the 1st fraction, since 7 × 8 = 56,
    21/7 = 21 × 8/7 × 8 = 168/56
  3. Likewise, for the 2nd fraction, since 8 × 7 = 56,
    15/8 = 15 × 7/8 × 7 = 105/56
  4. Add the two like fractions:
    168/56 + 105/56 = 168 + 105/56 = 273/56
  5. 273/56 simplified gives 39/8
  6. So, 21/7 + 15/8 = 39/8
    In mixed form: 47/8

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