Subtract 15/27 from 5/21
5/21 - 15/27 is -20/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 27 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 21 × 9 = 189,
5/21 = 5 × 9/21 × 9 = 45/189 - Likewise, for the 2nd fraction, since 27 × 7 = 189,
15/27 = 15 × 7/27 × 7 = 105/189 - Subtract the two like fractions:
45/189 - 105/189 = 45 - 105/189 = -60/189 - After reducing the fraction, the answer is -20/63
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