Add 12/8 and 25/21, Solve 1 4/8 + 1 4/21 as a fraction

Add 12/8 and 25/21

1^st number: 1 4/8, 2^nd number: 1 4/21

12/8 + 25/21 is 113/42.

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,
12/8 = 12 × 21/8 × 21 = 252/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
25/21 = 25 × 8/21 × 8 = 200/168
Add the two like fractions:
252/168 + 200/168 = 252 + 200/168 = 452/168
452/168 simplified gives 113/42
So, 12/8 + 25/21 = 113/42
In mixed form: 229/42

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