Subtract 42/54 from 18/45
18/45 - 42/54 is -17/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 54 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 45 × 6 = 270,
18/45 = 18 × 6/45 × 6 = 108/270 - Likewise, for the 2nd fraction, since 54 × 5 = 270,
42/54 = 42 × 5/54 × 5 = 210/270 - Subtract the two like fractions:
108/270 - 210/270 = 108 - 210/270 = -102/270 - After reducing the fraction, the answer is -17/45
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