Subtract 40/90 from 28/80
28/80 - 40/90 is -17/180.
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,
28/80 = 28 × 9/80 × 9 = 252/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
40/90 = 40 × 8/90 × 8 = 320/720 - Subtract the two like fractions:
252/720 - 320/720 = 252 - 320/720 = -68/720 - After reducing the fraction, the answer is -17/180
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