Add 81/21 and 27/54, Solve 3 18/21 + 27/54 as a fraction

Add 81/21 and 27/54

1^st number: 3 18/21, 2^nd number: 27/54

81/21 + 27/54 is 61/14.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 21 × 18 = 378,
81/21 = 81 × 18/21 × 18 = 1458/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
27/54 = 27 × 7/54 × 7 = 189/378
Add the two like fractions:
1458/378 + 189/378 = 1458 + 189/378 = 1647/378
1647/378 simplified gives 61/14
So, 81/21 + 27/54 = 61/14
In mixed form: 45/14

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