Add 12/21 and 42/84
12/21 + 42/84 is 15/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 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 84 × 1 = 84,
42/84 = 42 × 1/84 × 1 = 42/84 - Add the two like fractions:
48/84 + 42/84 = 48 + 42/84 = 90/84 - 90/84 simplified gives 15/14
- So, 12/21 + 42/84 = 15/14
In mixed form: 11/14
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