Add 81/21 and 20/12
1st number: 3 18/21, 2nd number: 1 8/12
81/21 + 20/12 is 116/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
81/21 = 81 × 4/21 × 4 = 324/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
20/12 = 20 × 7/12 × 7 = 140/84 - Add the two like fractions:
324/84 + 140/84 = 324 + 140/84 = 464/84 - 464/84 simplified gives 116/21
- So, 81/21 + 20/12 = 116/21
In mixed form: 511/21
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