Add 72/21 and 9/81, Solve 3 9/21 + 9/81 as a fraction

Add 72/21 and 9/81

1^st number: 3 9/21, 2^nd number: 9/81

72/21 + 9/81 is 223/63.

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,
72/21 = 72 × 27/21 × 27 = 1944/567
Likewise, for the 2nd fraction, since 81 × 7 = 567,
9/81 = 9 × 7/81 × 7 = 63/567
Add the two like fractions:
1944/567 + 63/567 = 1944 + 63/567 = 2007/567
2007/567 simplified gives 223/63
So, 72/21 + 9/81 = 223/63
In mixed form: 334/63

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