Subtract 42/63 from 30/84
30/84 - 42/63 is -13/42.
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,
30/84 = 30 × 3/84 × 3 = 90/252 - Likewise, for the 2nd fraction, since 63 × 4 = 252,
42/63 = 42 × 4/63 × 4 = 168/252 - Subtract the two like fractions:
90/252 - 168/252 = 90 - 168/252 = -78/252 - After reducing the fraction, the answer is -13/42
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