Subtract 10/21 from 10/27
10/27 - 10/21 is -20/189.
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,
10/27 = 10 × 7/27 × 7 = 70/189 - Likewise, for the 2nd fraction, since 21 × 9 = 189,
10/21 = 10 × 9/21 × 9 = 90/189 - Subtract the two like fractions:
70/189 - 90/189 = 70 - 90/189 = -20/189
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