Add 42/54 and 54/21, Solve 42/54 + 2 12/21 as a fraction

Add 42/54 and 54/21

1^st number: 42/54, 2^nd number: 2 12/21

42/54 + 54/21 is 211/63.

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,
42/54 = 42 × 7/54 × 7 = 294/378
Likewise, for the 2nd fraction, since 21 × 18 = 378,
54/21 = 54 × 18/21 × 18 = 972/378
Add the two like fractions:
294/378 + 972/378 = 294 + 972/378 = 1266/378
1266/378 simplified gives 211/63
So, 42/54 + 54/21 = 211/63
In mixed form: 322/63

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