Subtract 20/36 from 21/49
21/49 - 20/36 is -8/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 36 is 1764
Next, find the equivalent fraction of both fractional numbers with denominator 1764 - For the 1st fraction, since 49 × 36 = 1764,
21/49 = 21 × 36/49 × 36 = 756/1764 - Likewise, for the 2nd fraction, since 36 × 49 = 1764,
20/36 = 20 × 49/36 × 49 = 980/1764 - Subtract the two like fractions:
756/1764 - 980/1764 = 756 - 980/1764 = -224/1764 - After reducing the fraction, the answer is -8/63
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