Add 21/8 and 20/81
1st number: 2 5/8, 2nd number: 20/81
21/8 + 20/81 is 1861/648.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 8 × 81 = 648,
21/8 = 21 × 81/8 × 81 = 1701/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
20/81 = 20 × 8/81 × 8 = 160/648 - Add the two like fractions:
1701/648 + 160/648 = 1701 + 160/648 = 1861/648 - So, 21/8 + 20/81 = 1861/648
In mixed form: 2565/648
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