Add 5/8 and 42/21, Solve 5/8 + 2 0/21 as a fraction

Add 5/8 and 42/21

1^st number: 5/8, 2^nd number: 2 0/21

5/8 + 42/21 is 21/8.

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

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 8 × 21 = 168,
5/8 = 5 × 21/8 × 21 = 105/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
42/21 = 42 × 8/21 × 8 = 336/168
Add the two like fractions:
105/168 + 336/168 = 105 + 336/168 = 441/168
441/168 simplified gives 21/8
So, 5/8 + 42/21 = 21/8
In mixed form: 25/8

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