Add 21/28 and 81/7
1st number: 21/28, 2nd number: 11 4/7
21/28 + 81/7 is 345/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 7 is 28
Next, find the equivalent fraction of both fractional numbers with denominator 28 - For the 1st fraction, since 28 × 1 = 28,
21/28 = 21 × 1/28 × 1 = 21/28 - Likewise, for the 2nd fraction, since 7 × 4 = 28,
81/7 = 81 × 4/7 × 4 = 324/28 - Add the two like fractions:
21/28 + 324/28 = 21 + 324/28 = 345/28 - So, 21/28 + 81/7 = 345/28
In mixed form: 129/28
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