Subtract 20/63 from 3/42
3/42 - 20/63 is -31/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 63 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
3/42 = 3 × 3/42 × 3 = 9/126 - Likewise, for the 2nd fraction, since 63 × 2 = 126,
20/63 = 20 × 2/63 × 2 = 40/126 - Subtract the two like fractions:
9/126 - 40/126 = 9 - 40/126 = -31/126
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