Subtract 81/56 from 20/72
1st number: 20/72, 2nd number: 1 25/56
20/72 - 81/56 is -589/504.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 56 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
20/72 = 20 × 7/72 × 7 = 140/504 - Likewise, for the 2nd fraction, since 56 × 9 = 504,
81/56 = 81 × 9/56 × 9 = 729/504 - Subtract the two like fractions:
140/504 - 729/504 = 140 - 729/504 = -589/504
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