Subtract 28/80 from 20/90
20/90 - 28/80 is -23/180.
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,
20/90 = 20 × 8/90 × 8 = 160/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
28/80 = 28 × 9/80 × 9 = 252/720 - Subtract the two like fractions:
160/720 - 252/720 = 160 - 252/720 = -92/720 - After reducing the fraction, the answer is -23/180
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