Subtract 9/21 from 3/36
3/36 - 9/21 is -29/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 21 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
3/36 = 3 × 7/36 × 7 = 21/252 - Likewise, for the 2nd fraction, since 21 × 12 = 252,
9/21 = 9 × 12/21 × 12 = 108/252 - Subtract the two like fractions:
21/252 - 108/252 = 21 - 108/252 = -87/252 - After reducing the fraction, the answer is -29/84
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