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Add 81/80 and 21/90

1st number: 1 1/80, 2nd number: 21/90

81/80 + 21/90 is 299/240.

Steps for adding fractions

  1. Find the least common denominator or LCM of the two denominators:
    LCM of 80 and 90 is 720

    Next, find the equivalent fraction of both fractional numbers with denominator 720
  2. For the 1st fraction, since 80 × 9 = 720,
    81/80 = 81 × 9/80 × 9 = 729/720
  3. Likewise, for the 2nd fraction, since 90 × 8 = 720,
    21/90 = 21 × 8/90 × 8 = 168/720
  4. Add the two like fractions:
    729/720 + 168/720 = 729 + 168/720 = 897/720
  5. 897/720 simplified gives 299/240
  6. So, 81/80 + 21/90 = 299/240
    In mixed form: 159/240

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