Subtract 21/54 from 4/42
4/42 - 21/54 is -37/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 42 × 9 = 378,
4/42 = 4 × 9/42 × 9 = 36/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
21/54 = 21 × 7/54 × 7 = 147/378 - Subtract the two like fractions:
36/378 - 147/378 = 36 - 147/378 = -111/378 - After reducing the fraction, the answer is -37/126
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