Subtract 21/40 from 8/70
8/70 - 21/40 is -23/56.
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,
8/70 = 8 × 4/70 × 4 = 32/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Subtract the two like fractions:
32/280 - 147/280 = 32 - 147/280 = -115/280 - After reducing the fraction, the answer is -23/56
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