Subtract 1/81 from 21/56
21/56 - 1/81 is 235/648.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 81 is 4536
Next, find the equivalent fraction of both fractional numbers with denominator 4536 - For the 1st fraction, since 56 × 81 = 4536,
21/56 = 21 × 81/56 × 81 = 1701/4536 - Likewise, for the 2nd fraction, since 81 × 56 = 4536,
1/81 = 1 × 56/81 × 56 = 56/4536 - Subtract the two like fractions:
1701/4536 - 56/4536 = 1701 - 56/4536 = 1645/4536 - After reducing the fraction, the answer is 235/648
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