Add 4/12 and 3/21
4/12 + 3/21 is 10/21.
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,
4/12 = 4 × 7/12 × 7 = 28/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
3/21 = 3 × 4/21 × 4 = 12/84 - Add the two like fractions:
28/84 + 12/84 = 28 + 12/84 = 40/84 - 40/84 simplified gives 10/21
- So, 4/12 + 3/21 = 10/21
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