Add 28/12 and 20/21
1st number: 2 4/12, 2nd number: 20/21
28/12 + 20/21 is 23/7.
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,
28/12 = 28 × 7/12 × 7 = 196/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84 - Add the two like fractions:
196/84 + 80/84 = 196 + 80/84 = 276/84 - 276/84 simplified gives 23/7
- So, 28/12 + 20/21 = 23/7
In mixed form: 32/7
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