Add 1/12 and 28/21
1st number: 1/12, 2nd number: 1 7/21
1/12 + 28/21 is 17/12.
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,
1/12 = 1 × 7/12 × 7 = 7/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
28/21 = 28 × 4/21 × 4 = 112/84 - Add the two like fractions:
7/84 + 112/84 = 7 + 112/84 = 119/84 - 119/84 simplified gives 17/12
- So, 1/12 + 28/21 = 17/12
In mixed form: 15/12
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