Subtract 20/21 from 9/63
9/63 - 20/21 is -17/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 63 × 1 = 63,
9/63 = 9 × 1/63 × 1 = 9/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
20/21 = 20 × 3/21 × 3 = 60/63 - Subtract the two like fractions:
9/63 - 60/63 = 9 - 60/63 = -51/63 - After reducing the fraction, the answer is -17/21
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