Subtract 20/12 from 28/81
1st number: 28/81, 2nd number: 1 8/12
28/81 - 20/12 is -107/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 12 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 81 × 4 = 324,
28/81 = 28 × 4/81 × 4 = 112/324 - Likewise, for the 2nd fraction, since 12 × 27 = 324,
20/12 = 20 × 27/12 × 27 = 540/324 - Subtract the two like fractions:
112/324 - 540/324 = 112 - 540/324 = -428/324 - After reducing the fraction, the answer is -107/81
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