Subtract 8/21 from 12/54
12/54 - 8/21 is -10/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
12/54 = 12 × 7/54 × 7 = 84/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
8/21 = 8 × 18/21 × 18 = 144/378 - Subtract the two like fractions:
84/378 - 144/378 = 84 - 144/378 = -60/378 - After reducing the fraction, the answer is -10/63
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