Subtract 4/72 from 7/81
7/81 - 4/72 is 5/162.
Steps for subtracting 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,
7/81 = 7 × 8/81 × 8 = 56/648 - Likewise, for the 2nd fraction, since 72 × 9 = 648,
4/72 = 4 × 9/72 × 9 = 36/648 - Subtract the two like fractions:
56/648 - 36/648 = 56 - 36/648 = 20/648 - After reducing the fraction, the answer is 5/162
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