Subtract 7/8 from 18/40
18/40 - 7/8 is -17/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 8 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
18/40 = 18 × 1/40 × 1 = 18/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
7/8 = 7 × 5/8 × 5 = 35/40 - Subtract the two like fractions:
18/40 - 35/40 = 18 - 35/40 = -17/40
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