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

Add 90/21 and 4/54

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

90/21 + 4/54 is 824/189.

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,
4/54 = 4 × 7/54 × 7 = 28/378
Add the two like fractions:
1620/378 + 28/378 = 1620 + 28/378 = 1648/378
1648/378 simplified gives 824/189
So, 90/21 + 4/54 = 824/189
In mixed form: 468/189

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