Subtract 20/81 from 42/56
42/56 - 20/81 is 163/324.
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,
42/56 = 42 × 81/56 × 81 = 3402/4536 - Likewise, for the 2nd fraction, since 81 × 56 = 4536,
20/81 = 20 × 56/81 × 56 = 1120/4536 - Subtract the two like fractions:
3402/4536 - 1120/4536 = 3402 - 1120/4536 = 2282/4536 - After reducing the fraction, the answer is 163/324
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