Subtract 4/81 from 20/12
1st number: 1 8/12, 2nd number: 4/81
20/12 - 4/81 is 131/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 81 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 12 × 27 = 324,
20/12 = 20 × 27/12 × 27 = 540/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
4/81 = 4 × 4/81 × 4 = 16/324 - Subtract the two like fractions:
540/324 - 16/324 = 540 - 16/324 = 524/324 - After reducing the fraction, the answer is 131/81
- In mixed form: 150/81
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