Add 4/12 and 18/21
4/12 + 18/21 is 25/21.
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,
18/21 = 18 × 4/21 × 4 = 72/84 - Add the two like fractions:
28/84 + 72/84 = 28 + 72/84 = 100/84 - 100/84 simplified gives 25/21
- So, 4/12 + 18/21 = 25/21
In mixed form: 14/21
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