Subtract 12/40 from 4/20
4/20 - 12/40 is -1/10.
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,
4/20 = 4 × 2/20 × 2 = 8/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
12/40 = 12 × 1/40 × 1 = 12/40 - Subtract the two like fractions:
8/40 - 12/40 = 8 - 12/40 = -4/40 - After reducing the fraction, the answer is -1/10
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