Add 12/8 and 15/21
1st number: 1 4/8, 2nd number: 15/21
12/8 + 15/21 is 31/14.
Steps for adding fractions
- 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,
15/21 = 15 × 8/21 × 8 = 120/168 - Add the two like fractions:
252/168 + 120/168 = 252 + 120/168 = 372/168 - 372/168 simplified gives 31/14
- So, 12/8 + 15/21 = 31/14
In mixed form: 23/14
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