Subtract 18/12 from 42/40
1st number: 1 2/40, 2nd number: 1 6/12
42/40 - 18/12 is -9/20.
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,
42/40 = 42 × 3/40 × 3 = 126/120 - Likewise, for the 2nd fraction, since 12 × 10 = 120,
18/12 = 18 × 10/12 × 10 = 180/120 - Subtract the two like fractions:
126/120 - 180/120 = 126 - 180/120 = -54/120 - After reducing the fraction, the answer is -9/20
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