Subtract 42/54 from 3/21
3/21 - 42/54 is -40/63.
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,
3/21 = 3 × 18/21 × 18 = 54/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
42/54 = 42 × 7/54 × 7 = 294/378 - Subtract the two like fractions:
54/378 - 294/378 = 54 - 294/378 = -240/378 - After reducing the fraction, the answer is -40/63
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