Subtract 21/36 from 3/7
3/7 - 21/36 is -13/84.
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,
3/7 = 3 × 36/7 × 36 = 108/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
21/36 = 21 × 7/36 × 7 = 147/252 - Subtract the two like fractions:
108/252 - 147/252 = 108 - 147/252 = -39/252 - After reducing the fraction, the answer is -13/84
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