Add 90/21 and 12/54, Solve 4 6/21 + 12/54 as a fraction

Add 90/21 and 12/54

1^st number: 4 6/21, 2^nd number: 12/54

90/21 + 12/54 is 284/63.

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,
90/21 = 90 × 18/21 × 18 = 1620/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
12/54 = 12 × 7/54 × 7 = 84/378
Add the two like fractions:
1620/378 + 84/378 = 1620 + 84/378 = 1704/378
1704/378 simplified gives 284/63
So, 90/21 + 12/54 = 284/63
In mixed form: 432/63

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