Subtract 15/18 from 21/49
21/49 - 15/18 is -17/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 18 is 882
Next, find the equivalent fraction of both fractional numbers with denominator 882 - For the 1st fraction, since 49 × 18 = 882,
21/49 = 21 × 18/49 × 18 = 378/882 - Likewise, for the 2nd fraction, since 18 × 49 = 882,
15/18 = 15 × 49/18 × 49 = 735/882 - Subtract the two like fractions:
378/882 - 735/882 = 378 - 735/882 = -357/882 - After reducing the fraction, the answer is -17/42
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