Subtract 80/40 from 18/30
1st number: 18/30, 2nd number: 2 0/40
18/30 - 80/40 is -7/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
18/30 = 18 × 4/30 × 4 = 72/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
80/40 = 80 × 3/40 × 3 = 240/120 - Subtract the two like fractions:
72/120 - 240/120 = 72 - 240/120 = -168/120 - After reducing the fraction, the answer is -7/5
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