Subtract 21/49 from 7/18
7/18 - 21/49 is -5/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 49 is 882
Next, find the equivalent fraction of both fractional numbers with denominator 882 - For the 1st fraction, since 18 × 49 = 882,
7/18 = 7 × 49/18 × 49 = 343/882 - Likewise, for the 2nd fraction, since 49 × 18 = 882,
21/49 = 21 × 18/49 × 18 = 378/882 - Subtract the two like fractions:
343/882 - 378/882 = 343 - 378/882 = -35/882 - After reducing the fraction, the answer is -5/126
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