Add 4/81 and 70/21
1st number: 4/81, 2nd number: 3 7/21
4/81 + 70/21 is 274/81.
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,
4/81 = 4 × 7/81 × 7 = 28/567 - Likewise, for the 2nd fraction, since 21 × 27 = 567,
70/21 = 70 × 27/21 × 27 = 1890/567 - Add the two like fractions:
28/567 + 1890/567 = 28 + 1890/567 = 1918/567 - 1918/567 simplified gives 274/81
- So, 4/81 + 70/21 = 274/81
In mixed form: 331/81
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