Add 21/28 and 3/5
21/28 + 3/5 is 27/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 5 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 5 × 28 = 140,
3/5 = 3 × 28/5 × 28 = 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 + 3/5 = 27/20
In mixed form: 17/20
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