Subtract 45/18 from 42/80
1st number: 42/80, 2nd number: 2 9/18
42/80 - 45/18 is -79/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 18 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
42/80 = 42 × 9/80 × 9 = 378/720 - Likewise, for the 2nd fraction, since 18 × 40 = 720,
45/18 = 45 × 40/18 × 40 = 1800/720 - Subtract the two like fractions:
378/720 - 1800/720 = 378 - 1800/720 = -1422/720 - After reducing the fraction, the answer is -79/40
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