Subtract 18/28 from 3/40
3/40 - 18/28 is -159/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 28 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
3/40 = 3 × 7/40 × 7 = 21/280 - Likewise, for the 2nd fraction, since 28 × 10 = 280,
18/28 = 18 × 10/28 × 10 = 180/280 - Subtract the two like fractions:
21/280 - 180/280 = 21 - 180/280 = -159/280
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