Subtract 30/42 from 12/27
12/27 - 30/42 is -17/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 42 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 27 × 14 = 378,
12/27 = 12 × 14/27 × 14 = 168/378 - Likewise, for the 2nd fraction, since 42 × 9 = 378,
30/42 = 30 × 9/42 × 9 = 270/378 - Subtract the two like fractions:
168/378 - 270/378 = 168 - 270/378 = -102/378 - After reducing the fraction, the answer is -17/63
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