Subtract 21/40 from 18/35
18/35 - 21/40 is -3/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 35 × 8 = 280,
18/35 = 18 × 8/35 × 8 = 144/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Subtract the two like fractions:
144/280 - 147/280 = 144 - 147/280 = -3/280
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