Subtract 4/90 from 3/80
3/80 - 4/90 is -1/144.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 90 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
3/80 = 3 × 9/80 × 9 = 27/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
4/90 = 4 × 8/90 × 8 = 32/720 - Subtract the two like fractions:
27/720 - 32/720 = 27 - 32/720 = -5/720 - After reducing the fraction, the answer is -1/144
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