Subtract 40/90 from 40/80
40/80 - 40/90 is 1/18.
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,
40/80 = 40 × 9/80 × 9 = 360/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
40/90 = 40 × 8/90 × 8 = 320/720 - Subtract the two like fractions:
360/720 - 320/720 = 360 - 320/720 = 40/720 - After reducing the fraction, the answer is 1/18
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