Subtract 1/21 from 7/54
7/54 - 1/21 is 31/378.
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,
7/54 = 7 × 7/54 × 7 = 49/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
1/21 = 1 × 18/21 × 18 = 18/378 - Subtract the two like fractions:
49/378 - 18/378 = 49 - 18/378 = 31/378
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