Subtract 42/40 from 3/12
1st number: 3/12, 2nd number: 1 2/40
3/12 - 42/40 is -4/5.
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,
42/40 = 42 × 3/40 × 3 = 126/120 - Subtract the two like fractions:
30/120 - 126/120 = 30 - 126/120 = -96/120 - After reducing the fraction, the answer is -4/5
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