Add 21/8 and 81/28
1st number: 2 5/8, 2nd number: 2 25/28
21/8 + 81/28 is 309/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 28 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 8 × 7 = 56,
21/8 = 21 × 7/8 × 7 = 147/56 - Likewise, for the 2nd fraction, since 28 × 2 = 56,
81/28 = 81 × 2/28 × 2 = 162/56 - Add the two like fractions:
147/56 + 162/56 = 147 + 162/56 = 309/56 - So, 21/8 + 81/28 = 309/56
In mixed form: 529/56
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