Add 21/81 and 28/7
1st number: 21/81, 2nd number: 4 0/7
21/81 + 28/7 is 115/27.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 7 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
21/81 = 21 × 7/81 × 7 = 147/567 - Likewise, for the 2nd fraction, since 7 × 81 = 567,
28/7 = 28 × 81/7 × 81 = 2268/567 - Add the two like fractions:
147/567 + 2268/567 = 147 + 2268/567 = 2415/567 - 2415/567 simplified gives 115/27
- So, 21/81 + 28/7 = 115/27
In mixed form: 47/27
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