Subtract 18/30 from 7/40
7/40 - 18/30 is -17/40.
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,
7/40 = 7 × 3/40 × 3 = 21/120 - Likewise, for the 2nd fraction, since 30 × 4 = 120,
18/30 = 18 × 4/30 × 4 = 72/120 - Subtract the two like fractions:
21/120 - 72/120 = 21 - 72/120 = -51/120 - After reducing the fraction, the answer is -17/40
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