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Add 28/21 and 20/90

1st number: 1 7/21, 2nd number: 20/90

28/21 + 20/90 is 14/9.

Steps for adding fractions

  1. Find the least common denominator or LCM of the two denominators:
    LCM of 21 and 90 is 630

    Next, find the equivalent fraction of both fractional numbers with denominator 630
  2. For the 1st fraction, since 21 × 30 = 630,
    28/21 = 28 × 30/21 × 30 = 840/630
  3. Likewise, for the 2nd fraction, since 90 × 7 = 630,
    20/90 = 20 × 7/90 × 7 = 140/630
  4. Add the two like fractions:
    840/630 + 140/630 = 840 + 140/630 = 980/630
  5. 980/630 simplified gives 14/9
  6. So, 28/21 + 20/90 = 14/9
    In mixed form: 15/9

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