Subtract 18/81 from 56/72
56/72 - 18/81 is 5/9.
Steps for subtracting 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,
56/72 = 56 × 9/72 × 9 = 504/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
18/81 = 18 × 8/81 × 8 = 144/648 - Subtract the two like fractions:
504/648 - 144/648 = 504 - 144/648 = 360/648 - After reducing the fraction, the answer is 5/9
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