Add 28/12 and 54/21
1st number: 2 4/12, 2nd number: 2 12/21
28/12 + 54/21 is 103/21.
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,
28/12 = 28 × 7/12 × 7 = 196/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
54/21 = 54 × 4/21 × 4 = 216/84 - Add the two like fractions:
196/84 + 216/84 = 196 + 216/84 = 412/84 - 412/84 simplified gives 103/21
- So, 28/12 + 54/21 = 103/21
In mixed form: 419/21
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