Add 25/8 and 20/21
1st number: 3 1/8, 2nd number: 20/21
25/8 + 20/21 is 685/168.
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,
25/8 = 25 × 21/8 × 21 = 525/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
20/21 = 20 × 8/21 × 8 = 160/168 - Add the two like fractions:
525/168 + 160/168 = 525 + 160/168 = 685/168 - So, 25/8 + 20/21 = 685/168
In mixed form: 413/168
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