Add 28/21 and 7/81, Solve 1 7/21 + 7/81 as a fraction

Add 28/21 and 7/81

1^st number: 1 7/21, 2^nd number: 7/81

28/21 + 7/81 is 115/81.

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,
7/81 = 7 × 7/81 × 7 = 49/567
Add the two like fractions:
756/567 + 49/567 = 756 + 49/567 = 805/567
805/567 simplified gives 115/81
So, 28/21 + 7/81 = 115/81
In mixed form: 134/81

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