Subtract 42/45 from 20/54
20/54 - 42/45 is -76/135.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 45 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 54 × 5 = 270,
20/54 = 20 × 5/54 × 5 = 100/270 - Likewise, for the 2nd fraction, since 45 × 6 = 270,
42/45 = 42 × 6/45 × 6 = 252/270 - Subtract the two like fractions:
100/270 - 252/270 = 100 - 252/270 = -152/270 - After reducing the fraction, the answer is -76/135
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