Subtract 20/36 from 4/21
4/21 - 20/36 is -23/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 21 × 12 = 252,
4/21 = 4 × 12/21 × 12 = 48/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
20/36 = 20 × 7/36 × 7 = 140/252 - Subtract the two like fractions:
48/252 - 140/252 = 48 - 140/252 = -92/252 - After reducing the fraction, the answer is -23/63
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