Subtract 42/18 from 20/12
1st number: 1 8/12, 2nd number: 2 6/18
20/12 - 42/18 is -2/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 18 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 12 × 3 = 36,
20/12 = 20 × 3/12 × 3 = 60/36 - Likewise, for the 2nd fraction, since 18 × 2 = 36,
42/18 = 42 × 2/18 × 2 = 84/36 - Subtract the two like fractions:
60/36 - 84/36 = 60 - 84/36 = -24/36 - After reducing the fraction, the answer is -2/3
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