Answers

Subtract 20/70 from 15/80

15/80 - 20/70 is -11/112.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 70 is 560
   
   Next, find the equivalent fraction of both fractional numbers with denominator 560
2. For the 1st fraction, since 80 × 7 = 560,
   15/80 = 15 × 7/80 × 7 = 105/560
3. Likewise, for the 2nd fraction, since 70 × 8 = 560,
   20/70 = 20 × 8/70 × 8 = 160/560
4. Subtract the two like fractions:
   105/560 - 160/560 = 105 - 160/560 = -55/560
5. After reducing the fraction, the answer is -11/112

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