Subtract 45/30 from 18/40
1st number: 18/40, 2nd number: 1 15/30
18/40 - 45/30 is -21/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 30 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
18/40 = 18 × 3/40 × 3 = 54/120 - Likewise, for the 2nd fraction, since 30 × 4 = 120,
45/30 = 45 × 4/30 × 4 = 180/120 - Subtract the two like fractions:
54/120 - 180/120 = 54 - 180/120 = -126/120 - After reducing the fraction, the answer is -21/20
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