Subtract 18/20 from 1/2
1/2 - 18/20 is -2/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 20 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 2 × 10 = 20,
1/2 = 1 × 10/2 × 10 = 10/20 - Likewise, for the 2nd fraction, since 20 × 1 = 20,
18/20 = 18 × 1/20 × 1 = 18/20 - Subtract the two like fractions:
10/20 - 18/20 = 10 - 18/20 = -8/20 - After reducing the fraction, the answer is -2/5
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