Add 81/12 and 20/21
1st number: 6 9/12, 2nd number: 20/21
81/12 + 20/21 is 647/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
81/12 = 81 × 7/12 × 7 = 567/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84 - Add the two like fractions:
567/84 + 80/84 = 567 + 80/84 = 647/84 - So, 81/12 + 20/21 = 647/84
In mixed form: 759/84
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