Add 7/12 and 20/21
7/12 + 20/21 is 43/28.
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,
7/12 = 7 × 7/12 × 7 = 49/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84 - Add the two like fractions:
49/84 + 80/84 = 49 + 80/84 = 129/84 - 129/84 simplified gives 43/28
- So, 7/12 + 20/21 = 43/28
In mixed form: 115/28
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