Subtract 18/40 from 3/7
3/7 - 18/40 is -3/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 7 × 40 = 280,
3/7 = 3 × 40/7 × 40 = 120/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
18/40 = 18 × 7/40 × 7 = 126/280 - Subtract the two like fractions:
120/280 - 126/280 = 120 - 126/280 = -6/280 - After reducing the fraction, the answer is -3/140
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