Add 18/84 and 21/8, Solve 18/84 + 2 5/8 as a fraction

Add 18/84 and 21/8

1^st number: 18/84, 2^nd number: 2 5/8

18/84 + 21/8 is 159/56.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 8 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 84 × 2 = 168,
18/84 = 18 × 2/84 × 2 = 36/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
21/8 = 21 × 21/8 × 21 = 441/168
Add the two like fractions:
36/168 + 441/168 = 36 + 441/168 = 477/168
477/168 simplified gives 159/56
So, 18/84 + 21/8 = 159/56
In mixed form: 247/56

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