Subtract 20/12 from 42/27
1st number: 1 15/27, 2nd number: 1 8/12
42/27 - 20/12 is -1/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 12 is 108
Next, find the equivalent fraction of both fractional numbers with denominator 108 - For the 1st fraction, since 27 × 4 = 108,
42/27 = 42 × 4/27 × 4 = 168/108 - Likewise, for the 2nd fraction, since 12 × 9 = 108,
20/12 = 20 × 9/12 × 9 = 180/108 - Subtract the two like fractions:
168/108 - 180/108 = 168 - 180/108 = -12/108 - After reducing the fraction, the answer is -1/9
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