Subtract 21/63 from 20/80
20/80 - 21/63 is -1/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 63 is 5040
Next, find the equivalent fraction of both fractional numbers with denominator 5040 - For the 1st fraction, since 80 × 63 = 5040,
20/80 = 20 × 63/80 × 63 = 1260/5040 - Likewise, for the 2nd fraction, since 63 × 80 = 5040,
21/63 = 21 × 80/63 × 80 = 1680/5040 - Subtract the two like fractions:
1260/5040 - 1680/5040 = 1260 - 1680/5040 = -420/5040 - After reducing the fraction, the answer is -1/12
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