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Add 21/84 and 90/20

1st number: 21/84, 2nd number: 4 10/20

21/84 + 90/20 is 19/4.

Steps for adding fractions

  1. Find the least common denominator or LCM of the two denominators:
    LCM of 84 and 20 is 420

    Next, find the equivalent fraction of both fractional numbers with denominator 420
  2. For the 1st fraction, since 84 × 5 = 420,
    21/84 = 21 × 5/84 × 5 = 105/420
  3. Likewise, for the 2nd fraction, since 20 × 21 = 420,
    90/20 = 90 × 21/20 × 21 = 1890/420
  4. Add the two like fractions:
    105/420 + 1890/420 = 105 + 1890/420 = 1995/420
  5. 1995/420 simplified gives 19/4
  6. So, 21/84 + 90/20 = 19/4
    In mixed form: 43/4

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