Add 81/54 and 4/21, Solve 1 27/54 + 4/21 as a fraction

Add 81/54 and 4/21

1^st number: 1 27/54, 2^nd number: 4/21

81/54 + 4/21 is 71/42.

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

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 54 × 7 = 378,
81/54 = 81 × 7/54 × 7 = 567/378
Likewise, for the 2nd fraction, since 21 × 18 = 378,
4/21 = 4 × 18/21 × 18 = 72/378
Add the two like fractions:
567/378 + 72/378 = 567 + 72/378 = 639/378
639/378 simplified gives 71/42
So, 81/54 + 4/21 = 71/42
In mixed form: 129/42

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