Subtract 21/36 from 4/7
4/7 - 21/36 is -1/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 7 × 36 = 252,
4/7 = 4 × 36/7 × 36 = 144/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
21/36 = 21 × 7/36 × 7 = 147/252 - Subtract the two like fractions:
144/252 - 147/252 = 144 - 147/252 = -3/252 - After reducing the fraction, the answer is -1/84
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