Subtract 12/20 from 42/80
42/80 - 12/20 is -3/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 20 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
42/80 = 42 × 1/80 × 1 = 42/80 - Likewise, for the 2nd fraction, since 20 × 4 = 80,
12/20 = 12 × 4/20 × 4 = 48/80 - Subtract the two like fractions:
42/80 - 48/80 = 42 - 48/80 = -6/80 - After reducing the fraction, the answer is -3/40
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