Subtract 81/28 from 12/20
1st number: 12/20, 2nd number: 2 25/28
12/20 - 81/28 is -321/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 28 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
12/20 = 12 × 7/20 × 7 = 84/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
81/28 = 81 × 5/28 × 5 = 405/140 - Subtract the two like fractions:
84/140 - 405/140 = 84 - 405/140 = -321/140
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