Add 21/12 and 20/7
1st number: 1 9/12, 2nd number: 2 6/7
21/12 + 20/7 is 129/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 7 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 7 × 12 = 84,
20/7 = 20 × 12/7 × 12 = 240/84 - Add the two like fractions:
147/84 + 240/84 = 147 + 240/84 = 387/84 - 387/84 simplified gives 129/28
- So, 21/12 + 20/7 = 129/28
In mixed form: 417/28
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