Add 42/12 and 81/21
1st number: 3 6/12, 2nd number: 3 18/21
42/12 + 81/21 is 103/14.
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,
42/12 = 42 × 7/12 × 7 = 294/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
81/21 = 81 × 4/21 × 4 = 324/84 - Add the two like fractions:
294/84 + 324/84 = 294 + 324/84 = 618/84 - 618/84 simplified gives 103/14
- So, 42/12 + 81/21 = 103/14
In mixed form: 75/14
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