Subtract 15/20 from 15/40
15/40 - 15/20 is -3/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 20 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
15/40 = 15 × 1/40 × 1 = 15/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
15/20 = 15 × 2/20 × 2 = 30/40 - Subtract the two like fractions:
15/40 - 30/40 = 15 - 30/40 = -15/40 - After reducing the fraction, the answer is -3/8
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