Add 21/8 and 54/42, Solve 2 5/8 + 1 12/42 as a fraction

Add 21/8 and 54/42

1^st number: 2 5/8, 2^nd number: 1 12/42

21/8 + 54/42 is 219/56.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 42 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 8 × 21 = 168,
21/8 = 21 × 21/8 × 21 = 441/168
Likewise, for the 2nd fraction, since 42 × 4 = 168,
54/42 = 54 × 4/42 × 4 = 216/168
Add the two like fractions:
441/168 + 216/168 = 441 + 216/168 = 657/168
657/168 simplified gives 219/56
So, 21/8 + 54/42 = 219/56
In mixed form: 351/56

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