Add 81/21 and 2/12
1st number: 3 18/21, 2nd number: 2/12
81/21 + 2/12 is 169/42.
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,
2/12 = 2 × 7/12 × 7 = 14/84 - Add the two like fractions:
324/84 + 14/84 = 324 + 14/84 = 338/84 - 338/84 simplified gives 169/42
- So, 81/21 + 2/12 = 169/42
In mixed form: 41/42
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