Subtract 42/12 from 30/40
1st number: 30/40, 2nd number: 3 6/12
30/40 - 42/12 is -11/4.
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,
30/40 = 30 × 3/40 × 3 = 90/120 - Likewise, for the 2nd fraction, since 12 × 10 = 120,
42/12 = 42 × 10/12 × 10 = 420/120 - Subtract the two like fractions:
90/120 - 420/120 = 90 - 420/120 = -330/120 - After reducing the fraction, the answer is -11/4
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