Subtract 81/20 from 20/12
1st number: 1 8/12, 2nd number: 4 1/20
20/12 - 81/20 is -143/60.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 20 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
20/12 = 20 × 5/12 × 5 = 100/60 - Likewise, for the 2nd fraction, since 20 × 3 = 60,
81/20 = 81 × 3/20 × 3 = 243/60 - Subtract the two like fractions:
100/60 - 243/60 = 100 - 243/60 = -143/60
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