Subtract 15/36 from 12/21
12/21 - 15/36 is 13/84.
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,
12/21 = 12 × 12/21 × 12 = 144/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
15/36 = 15 × 7/36 × 7 = 105/252 - Subtract the two like fractions:
144/252 - 105/252 = 144 - 105/252 = 39/252 - After reducing the fraction, the answer is 13/84
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