Subtract 20/21 from 7/63
7/63 - 20/21 is -53/63.
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,
7/63 = 7 × 1/63 × 1 = 7/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
20/21 = 20 × 3/21 × 3 = 60/63 - Subtract the two like fractions:
7/63 - 60/63 = 7 - 60/63 = -53/63
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