Subtract 18/20 from 15/40
15/40 - 18/20 is -21/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 20 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
15/40 = 15 × 1/40 × 1 = 15/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
18/20 = 18 × 2/20 × 2 = 36/40 - Subtract the two like fractions:
15/40 - 36/40 = 15 - 36/40 = -21/40
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