Add 27/12 and 54/21
1st number: 2 3/12, 2nd number: 2 12/21
27/12 + 54/21 is 135/28.
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,
27/12 = 27 × 7/12 × 7 = 189/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
54/21 = 54 × 4/21 × 4 = 216/84 - Add the two like fractions:
189/84 + 216/84 = 189 + 216/84 = 405/84 - 405/84 simplified gives 135/28
- So, 27/12 + 54/21 = 135/28
In mixed form: 423/28
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