Subtract 81/20 from 12/28
1st number: 12/28, 2nd number: 4 1/20
12/28 - 81/20 is -507/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
12/28 = 12 × 5/28 × 5 = 60/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
81/20 = 81 × 7/20 × 7 = 567/140 - Subtract the two like fractions:
60/140 - 567/140 = 60 - 567/140 = -507/140
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