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

Add 18/21 and 21/8

1^st number: 18/21, 2^nd number: 2 5/8

18/21 + 21/8 is 195/56.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
18/21 = 18 × 8/21 × 8 = 144/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
21/8 = 21 × 21/8 × 21 = 441/168
Add the two like fractions:
144/168 + 441/168 = 144 + 441/168 = 585/168
585/168 simplified gives 195/56
So, 18/21 + 21/8 = 195/56
In mixed form: 327/56

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