Add 21/28 and 81/35
1st number: 21/28, 2nd number: 2 11/35
21/28 + 81/35 is 429/140.
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,
81/35 = 81 × 4/35 × 4 = 324/140 - Add the two like fractions:
105/140 + 324/140 = 105 + 324/140 = 429/140 - So, 21/28 + 81/35 = 429/140
In mixed form: 39/140
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