Answers

Subtract 70/80 from 28/36

28/36 - 70/80 is -7/72.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 36 and 80 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 36 × 20 = 720,
   28/36 = 28 × 20/36 × 20 = 560/720
3. Likewise, for the 2nd fraction, since 80 × 9 = 720,
   70/80 = 70 × 9/80 × 9 = 630/720
4. Subtract the two like fractions:
   560/720 - 630/720 = 560 - 630/720 = -70/720
5. After reducing the fraction, the answer is -7/72

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