Add 81/21 and 21/28
1st number: 3 18/21, 2nd number: 21/28
81/21 + 21/28 is 129/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
81/21 = 81 × 4/21 × 4 = 324/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
21/28 = 21 × 3/28 × 3 = 63/84 - Add the two like fractions:
324/84 + 63/84 = 324 + 63/84 = 387/84 - 387/84 simplified gives 129/28
- So, 81/21 + 21/28 = 129/28
In mixed form: 417/28
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