Subtract 20/40 from 15/70
15/70 - 20/40 is -2/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 70 × 4 = 280,
15/70 = 15 × 4/70 × 4 = 60/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
20/40 = 20 × 7/40 × 7 = 140/280 - Subtract the two like fractions:
60/280 - 140/280 = 60 - 140/280 = -80/280 - After reducing the fraction, the answer is -2/7
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