Subtract 45/12 from 20/42
1st number: 20/42, 2nd number: 3 9/12
20/42 - 45/12 is -275/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
20/42 = 20 × 2/42 × 2 = 40/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
45/12 = 45 × 7/12 × 7 = 315/84 - Subtract the two like fractions:
40/84 - 315/84 = 40 - 315/84 = -275/84
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