Subtract 20/40 from 9/20
9/20 - 20/40 is -1/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 20 × 2 = 40,
9/20 = 9 × 2/20 × 2 = 18/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
20/40 = 20 × 1/40 × 1 = 20/40 - Subtract the two like fractions:
18/40 - 20/40 = 18 - 20/40 = -2/40 - After reducing the fraction, the answer is -1/20
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