Subtract 28/70 from 15/40
15/40 - 28/70 is -1/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 70 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 70 × 4 = 280,
28/70 = 28 × 4/70 × 4 = 112/280 - Subtract the two like fractions:
105/280 - 112/280 = 105 - 112/280 = -7/280 - After reducing the fraction, the answer is -1/40
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