Subtract 4/81 from 7/72
7/72 - 4/81 is 31/648.
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,
7/72 = 7 × 9/72 × 9 = 63/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
4/81 = 4 × 8/81 × 8 = 32/648 - Subtract the two like fractions:
63/648 - 32/648 = 63 - 32/648 = 31/648
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