Add 21/28 and 28/35
21/28 + 28/35 is 31/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 35 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
21/28 = 21 × 5/28 × 5 = 105/140 - Likewise, for the 2nd fraction, since 35 × 4 = 140,
28/35 = 28 × 4/35 × 4 = 112/140 - Add the two like fractions:
105/140 + 112/140 = 105 + 112/140 = 217/140 - 217/140 simplified gives 31/20
- So, 21/28 + 28/35 = 31/20
In mixed form: 111/20
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