Add 21/42 and 12/28
21/42 + 12/28 is 13/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
12/28 = 12 × 3/28 × 3 = 36/84 - Add the two like fractions:
42/84 + 36/84 = 42 + 36/84 = 78/84 - 78/84 simplified gives 13/14
- So, 21/42 + 12/28 = 13/14
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