Add 12/21 and 15/28
12/21 + 15/28 is 31/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
12/21 = 12 × 4/21 × 4 = 48/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
15/28 = 15 × 3/28 × 3 = 45/84 - Add the two like fractions:
48/84 + 45/84 = 48 + 45/84 = 93/84 - 93/84 simplified gives 31/28
- So, 12/21 + 15/28 = 31/28
In mixed form: 13/28
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