Subtract 9/80 from 8/90
8/90 - 9/80 is -17/720.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
8/90 = 8 × 8/90 × 8 = 64/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
9/80 = 9 × 9/80 × 9 = 81/720 - Subtract the two like fractions:
64/720 - 81/720 = 64 - 81/720 = -17/720
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