Add 20/21 and 15/8
1st number: 20/21, 2nd number: 1 7/8
20/21 + 15/8 is 475/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
20/21 = 20 × 8/21 × 8 = 160/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
15/8 = 15 × 21/8 × 21 = 315/168 - Add the two like fractions:
160/168 + 315/168 = 160 + 315/168 = 475/168 - So, 20/21 + 15/8 = 475/168
In mixed form: 2139/168
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