Add 28/21 and 70/81
1st number: 1 7/21, 2nd number: 70/81
28/21 + 70/81 is 178/81.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
28/21 = 28 × 27/21 × 27 = 756/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
70/81 = 70 × 7/81 × 7 = 490/567 - Add the two like fractions:
756/567 + 490/567 = 756 + 490/567 = 1246/567 - 1246/567 simplified gives 178/81
- So, 28/21 + 70/81 = 178/81
In mixed form: 216/81
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