Subtract 3/7 from 15/40
15/40 - 3/7 is -3/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 7 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
15/40 = 15 × 7/40 × 7 = 105/280 - Likewise, for the 2nd fraction, since 7 × 40 = 280,
3/7 = 3 × 40/7 × 40 = 120/280 - Subtract the two like fractions:
105/280 - 120/280 = 105 - 120/280 = -15/280 - After reducing the fraction, the answer is -3/56
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