Subtract 1/21 from 1/27
1/27 - 1/21 is -2/189.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 21 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 27 × 7 = 189,
1/27 = 1 × 7/27 × 7 = 7/189 - Likewise, for the 2nd fraction, since 21 × 9 = 189,
1/21 = 1 × 9/21 × 9 = 9/189 - Subtract the two like fractions:
7/189 - 9/189 = 7 - 9/189 = -2/189
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