Add 20/72 and 56/81
20/72 + 56/81 is 157/162.
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,
56/81 = 56 × 8/81 × 8 = 448/648 - Add the two like fractions:
180/648 + 448/648 = 180 + 448/648 = 628/648 - 628/648 simplified gives 157/162
- So, 20/72 + 56/81 = 157/162
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