Add 21/12 and 27/42
1st number: 1 9/12, 2nd number: 27/42
21/12 + 27/42 is 67/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
21/12 = 21 × 7/12 × 7 = 147/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
27/42 = 27 × 2/42 × 2 = 54/84 - Add the two like fractions:
147/84 + 54/84 = 147 + 54/84 = 201/84 - 201/84 simplified gives 67/28
- So, 21/12 + 27/42 = 67/28
In mixed form: 211/28
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