Add 42/84 and 21/27
42/84 + 21/27 is 23/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 27 is 756
Next, find the equivalent fraction of both fractional numbers with denominator 756 - For the 1st fraction, since 84 × 9 = 756,
42/84 = 42 × 9/84 × 9 = 378/756 - Likewise, for the 2nd fraction, since 27 × 28 = 756,
21/27 = 21 × 28/27 × 28 = 588/756 - Add the two like fractions:
378/756 + 588/756 = 378 + 588/756 = 966/756 - 966/756 simplified gives 23/18
- So, 42/84 + 21/27 = 23/18
In mixed form: 15/18
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