Subtract 21/27 from 20/63
20/63 - 21/27 is -29/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 27 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 63 × 3 = 189,
20/63 = 20 × 3/63 × 3 = 60/189 - Likewise, for the 2nd fraction, since 27 × 7 = 189,
21/27 = 21 × 7/27 × 7 = 147/189 - Subtract the two like fractions:
60/189 - 147/189 = 60 - 147/189 = -87/189 - After reducing the fraction, the answer is -29/63
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