Add 20/72 and 9/81
20/72 + 9/81 is 7/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 72 × 9 = 648,
20/72 = 20 × 9/72 × 9 = 180/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
9/81 = 9 × 8/81 × 8 = 72/648 - Add the two like fractions:
180/648 + 72/648 = 180 + 72/648 = 252/648 - 252/648 simplified gives 7/18
- So, 20/72 + 9/81 = 7/18
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