Subtract 18/27 from 21/49
21/49 - 18/27 is -5/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 27 is 1323
Next, find the equivalent fraction of both fractional numbers with denominator 1323 - For the 1st fraction, since 49 × 27 = 1323,
21/49 = 21 × 27/49 × 27 = 567/1323 - Likewise, for the 2nd fraction, since 27 × 49 = 1323,
18/27 = 18 × 49/27 × 49 = 882/1323 - Subtract the two like fractions:
567/1323 - 882/1323 = 567 - 882/1323 = -315/1323 - After reducing the fraction, the answer is -5/21
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