Add 20/81 and 21/72
20/81 + 21/72 is 349/648.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 72 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 81 × 8 = 648,
20/81 = 20 × 8/81 × 8 = 160/648 - Likewise, for the 2nd fraction, since 72 × 9 = 648,
21/72 = 21 × 9/72 × 9 = 189/648 - Add the two like fractions:
160/648 + 189/648 = 160 + 189/648 = 349/648 - So, 20/81 + 21/72 = 349/648
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