Answers

Subtract 42/80 from 28/72

28/72 - 42/80 is -49/360.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 72 and 80 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 72 × 10 = 720,
   28/72 = 28 × 10/72 × 10 = 280/720
3. Likewise, for the 2nd fraction, since 80 × 9 = 720,
   42/80 = 42 × 9/80 × 9 = 378/720
4. Subtract the two like fractions:
   280/720 - 378/720 = 280 - 378/720 = -98/720
5. After reducing the fraction, the answer is -49/360

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