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Add 12/90 and 3/21

12/90 + 3/21 is 29/105.

Steps for adding fractions

  1. Find the least common denominator or LCM of the two denominators:
    LCM of 90 and 21 is 630
  2. For the 1st fraction, since 90 × 7 = 630,
    12/90 = 12 × 7/90 × 7 = 84/630
  3. Likewise, for the 2nd fraction, since 21 × 30 = 630,
    3/21 = 3 × 30/21 × 30 = 90/630
  4. Add the two fractions:
    84/630 + 90/630 = 84 + 90/630 = 174/630
  5. 174/630 simplified gives 29/105
  6. So, 12/90 + 3/21 = 29/105

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