Subtract 18/40 from 3/12
3/12 - 18/40 is -1/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 12 × 10 = 120,
3/12 = 3 × 10/12 × 10 = 30/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
18/40 = 18 × 3/40 × 3 = 54/120 - Subtract the two like fractions:
30/120 - 54/120 = 30 - 54/120 = -24/120 - After reducing the fraction, the answer is -1/5
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