Add 12/28 and 3/21
12/28 + 3/21 is 4/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
12/28 = 12 × 3/28 × 3 = 36/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
3/21 = 3 × 4/21 × 4 = 12/84 - Add the two like fractions:
36/84 + 12/84 = 36 + 12/84 = 48/84 - 48/84 simplified gives 4/7
- So, 12/28 + 3/21 = 4/7
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