Add 21/15 and 28/54
1st number: 1 6/15, 2nd number: 28/54
21/15 + 28/54 is 259/135.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 54 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 15 × 18 = 270,
21/15 = 21 × 18/15 × 18 = 378/270 - Likewise, for the 2nd fraction, since 54 × 5 = 270,
28/54 = 28 × 5/54 × 5 = 140/270 - Add the two like fractions:
378/270 + 140/270 = 378 + 140/270 = 518/270 - 518/270 simplified gives 259/135
- So, 21/15 + 28/54 = 259/135
In mixed form: 1124/135
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