Add 80/21 and 21/81, Solve 3 17/21 + 21/81 as a fraction

Add 80/21 and 21/81

1^st number: 3 17/21, 2^nd number: 21/81

80/21 + 21/81 is 769/189.

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,
80/21 = 80 × 27/21 × 27 = 2160/567
Likewise, for the 2nd fraction, since 81 × 7 = 567,
21/81 = 21 × 7/81 × 7 = 147/567
Add the two like fractions:
2160/567 + 147/567 = 2160 + 147/567 = 2307/567
2307/567 simplified gives 769/189
So, 80/21 + 21/81 = 769/189
In mixed form: 413/189

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