Add 21/28 and 20/12
1st number: 21/28, 2nd number: 1 8/12
21/28 + 20/12 is 29/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
21/28 = 21 × 3/28 × 3 = 63/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
20/12 = 20 × 7/12 × 7 = 140/84 - Add the two like fractions:
63/84 + 140/84 = 63 + 140/84 = 203/84 - 203/84 simplified gives 29/12
- So, 21/28 + 20/12 = 29/12
In mixed form: 25/12
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