Subtract 42/63 from 20/84
20/84 - 42/63 is -3/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 63 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 84 × 3 = 252,
20/84 = 20 × 3/84 × 3 = 60/252 - Likewise, for the 2nd fraction, since 63 × 4 = 252,
42/63 = 42 × 4/63 × 4 = 168/252 - Subtract the two like fractions:
60/252 - 168/252 = 60 - 168/252 = -108/252 - After reducing the fraction, the answer is -3/7
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