Subtract 21/7 from 21/27
1st number: 21/27, 2nd number: 3 0/7
21/27 - 21/7 is -20/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 7 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 27 × 7 = 189,
21/27 = 21 × 7/27 × 7 = 147/189 - Likewise, for the 2nd fraction, since 7 × 27 = 189,
21/7 = 21 × 27/7 × 27 = 567/189 - Subtract the two like fractions:
147/189 - 567/189 = 147 - 567/189 = -420/189 - After reducing the fraction, the answer is -20/9
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