Subtract 9/12 from 20/40
20/40 - 9/12 is -1/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 12 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
20/40 = 20 × 3/40 × 3 = 60/120 - Likewise, for the 2nd fraction, since 12 × 10 = 120,
9/12 = 9 × 10/12 × 10 = 90/120 - Subtract the two like fractions:
60/120 - 90/120 = 60 - 90/120 = -30/120 - After reducing the fraction, the answer is -1/4
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