Subtract 42/7 from 18/40
1st number: 18/40, 2nd number: 6 0/7
18/40 - 42/7 is -111/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 7 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
18/40 = 18 × 7/40 × 7 = 126/280 - Likewise, for the 2nd fraction, since 7 × 40 = 280,
42/7 = 42 × 40/7 × 40 = 1680/280 - Subtract the two like fractions:
126/280 - 1680/280 = 126 - 1680/280 = -1554/280 - After reducing the fraction, the answer is -111/20
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