Subtract 7/21 from 9/54
9/54 - 7/21 is -1/6.
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,
9/54 = 9 × 7/54 × 7 = 63/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
7/21 = 7 × 18/21 × 18 = 126/378 - Subtract the two like fractions:
63/378 - 126/378 = 63 - 126/378 = -63/378 - After reducing the fraction, the answer is -1/6
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