Add 21/5 and 28/54, Solve 4 1/5 + 28/54 as a fraction

Add 21/5 and 28/54

1^st number: 4 1/5, 2^nd number: 28/54

21/5 + 28/54 is 637/135.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 54 is 270

Next, find the equivalent fraction of both fractional numbers with denominator 270
For the 1st fraction, since 5 × 54 = 270,
21/5 = 21 × 54/5 × 54 = 1134/270
Likewise, for the 2nd fraction, since 54 × 5 = 270,
28/54 = 28 × 5/54 × 5 = 140/270
Add the two like fractions:
1134/270 + 140/270 = 1134 + 140/270 = 1274/270
1274/270 simplified gives 637/135
So, 21/5 + 28/54 = 637/135
In mixed form: 497/135

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