Subtract 81/72 from 20/12
1st number: 1 8/12, 2nd number: 1 9/72
20/12 - 81/72 is 13/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 12 × 6 = 72,
20/12 = 20 × 6/12 × 6 = 120/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
81/72 = 81 × 1/72 × 1 = 81/72 - Subtract the two like fractions:
120/72 - 81/72 = 120 - 81/72 = 39/72 - After reducing the fraction, the answer is 13/24
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