Subtract 18/54 from 4/21
4/21 - 18/54 is -1/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 21 × 18 = 378,
4/21 = 4 × 18/21 × 18 = 72/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
18/54 = 18 × 7/54 × 7 = 126/378 - Subtract the two like fractions:
72/378 - 126/378 = 72 - 126/378 = -54/378 - After reducing the fraction, the answer is -1/7
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