Subtract 18/30 from 3/40
3/40 - 18/30 is -21/40.
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,
3/40 = 3 × 3/40 × 3 = 9/120 - Likewise, for the 2nd fraction, since 30 × 4 = 120,
18/30 = 18 × 4/30 × 4 = 72/120 - Subtract the two like fractions:
9/120 - 72/120 = 9 - 72/120 = -63/120 - After reducing the fraction, the answer is -21/40
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