Subtract 63/70 from 18/40
18/40 - 63/70 is -9/20.
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,
18/40 = 18 × 7/40 × 7 = 126/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
63/70 = 63 × 4/70 × 4 = 252/280 - Subtract the two like fractions:
126/280 - 252/280 = 126 - 252/280 = -126/280 - After reducing the fraction, the answer is -9/20
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