Add 21/28 and 21/35
21/28 + 21/35 is 27/20.
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,
21/35 = 21 × 4/35 × 4 = 84/140 - Add the two like fractions:
105/140 + 84/140 = 105 + 84/140 = 189/140 - 189/140 simplified gives 27/20
- So, 21/28 + 21/35 = 27/20
In mixed form: 17/20
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