Subtract 15/21 from 18/36
18/36 - 15/21 is -3/14.
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,
18/36 = 18 × 7/36 × 7 = 126/252 - Likewise, for the 2nd fraction, since 21 × 12 = 252,
15/21 = 15 × 12/21 × 12 = 180/252 - Subtract the two like fractions:
126/252 - 180/252 = 126 - 180/252 = -54/252 - After reducing the fraction, the answer is -3/14
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