Subtract 18/80 from 4/20
4/20 - 18/80 is -1/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 20 × 4 = 80,
4/20 = 4 × 4/20 × 4 = 16/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
18/80 = 18 × 1/80 × 1 = 18/80 - Subtract the two like fractions:
16/80 - 18/80 = 16 - 18/80 = -2/80 - After reducing the fraction, the answer is -1/40
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