Subtract 4/36 from 1/21
1/21 - 4/36 is -4/63.
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,
1/21 = 1 × 12/21 × 12 = 12/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
4/36 = 4 × 7/36 × 7 = 28/252 - Subtract the two like fractions:
12/252 - 28/252 = 12 - 28/252 = -16/252 - After reducing the fraction, the answer is -4/63
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