Subtract 8/20 from 7/40
7/40 - 8/20 is -9/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 20 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
7/40 = 7 × 1/40 × 1 = 7/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
8/20 = 8 × 2/20 × 2 = 16/40 - Subtract the two like fractions:
7/40 - 16/40 = 7 - 16/40 = -9/40
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