Subtract 20/35 from 21/63
21/63 - 20/35 is -5/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 35 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 63 × 5 = 315,
21/63 = 21 × 5/63 × 5 = 105/315 - Likewise, for the 2nd fraction, since 35 × 9 = 315,
20/35 = 20 × 9/35 × 9 = 180/315 - Subtract the two like fractions:
105/315 - 180/315 = 105 - 180/315 = -75/315 - After reducing the fraction, the answer is -5/21
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