Subtract 42/80 from 18/45
18/45 - 42/80 is -1/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 45 × 16 = 720,
18/45 = 18 × 16/45 × 16 = 288/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
42/80 = 42 × 9/80 × 9 = 378/720 - Subtract the two like fractions:
288/720 - 378/720 = 288 - 378/720 = -90/720 - After reducing the fraction, the answer is -1/8
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