Add 7/81 and 70/21
1st number: 7/81, 2nd number: 3 7/21
7/81 + 70/21 is 277/81.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 21 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
7/81 = 7 × 7/81 × 7 = 49/567 - Likewise, for the 2nd fraction, since 21 × 27 = 567,
70/21 = 70 × 27/21 × 27 = 1890/567 - Add the two like fractions:
49/567 + 1890/567 = 49 + 1890/567 = 1939/567 - 1939/567 simplified gives 277/81
- So, 7/81 + 70/21 = 277/81
In mixed form: 334/81
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