Subtract 42/63 from 40/84
40/84 - 42/63 is -4/21.
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,
40/84 = 40 × 3/84 × 3 = 120/252 - Likewise, for the 2nd fraction, since 63 × 4 = 252,
42/63 = 42 × 4/63 × 4 = 168/252 - Subtract the two like fractions:
120/252 - 168/252 = 120 - 168/252 = -48/252 - After reducing the fraction, the answer is -4/21
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