Subtract 18/21 from 3/54
3/54 - 18/21 is -101/126.
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,
3/54 = 3 × 7/54 × 7 = 21/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
18/21 = 18 × 18/21 × 18 = 324/378 - Subtract the two like fractions:
21/378 - 324/378 = 21 - 324/378 = -303/378 - After reducing the fraction, the answer is -101/126
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