Subtract 12/15 from 30/40
30/40 - 12/15 is -1/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 15 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 15 × 8 = 120,
12/15 = 12 × 8/15 × 8 = 96/120 - Subtract the two like fractions:
90/120 - 96/120 = 90 - 96/120 = -6/120 - After reducing the fraction, the answer is -1/20
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