Add 21/56 and 42/21, Solve 21/56 + 2 0/21 as a fraction

Add 21/56 and 42/21

1^st number: 21/56, 2^nd number: 2 0/21

21/56 + 42/21 is 19/8.

Find the least common denominator or LCM of the two denominators:
LCM of 56 and 21 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 56 × 3 = 168,
21/56 = 21 × 3/56 × 3 = 63/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
42/21 = 42 × 8/21 × 8 = 336/168
Add the two like fractions:
63/168 + 336/168 = 63 + 336/168 = 399/168
399/168 simplified gives 19/8
So, 21/56 + 42/21 = 19/8
In mixed form: 23/8

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