Subtract 40/45 from 28/80
28/80 - 40/45 is -97/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 45 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 45 × 16 = 720,
40/45 = 40 × 16/45 × 16 = 640/720 - Subtract the two like fractions:
252/720 - 640/720 = 252 - 640/720 = -388/720 - After reducing the fraction, the answer is -97/180
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