Add 21/81 and 18/8
1st number: 21/81, 2nd number: 2 2/8
21/81 + 18/8 is 271/108.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 8 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 81 × 8 = 648,
21/81 = 21 × 8/81 × 8 = 168/648 - Likewise, for the 2nd fraction, since 8 × 81 = 648,
18/8 = 18 × 81/8 × 81 = 1458/648 - Add the two like fractions:
168/648 + 1458/648 = 168 + 1458/648 = 1626/648 - 1626/648 simplified gives 271/108
- So, 21/81 + 18/8 = 271/108
In mixed form: 255/108
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