Add 3/12 and 18/21
3/12 + 18/21 is 31/28.
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,
3/12 = 3 × 7/12 × 7 = 21/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
18/21 = 18 × 4/21 × 4 = 72/84 - Add the two like fractions:
21/84 + 72/84 = 21 + 72/84 = 93/84 - 93/84 simplified gives 31/28
- So, 3/12 + 18/21 = 31/28
In mixed form: 13/28
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