Answers

Subtract 90/70 from 30/80

1^st number: 30/80, 2^nd number: 1 20/70

30/80 - 90/70 is -51/56.

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,
   30/80 = 30 × 7/80 × 7 = 210/560
3. Likewise, for the 2nd fraction, since 70 × 8 = 560,
   90/70 = 90 × 8/70 × 8 = 720/560
4. Subtract the two like fractions:
   210/560 - 720/560 = 210 - 720/560 = -510/560
5. After reducing the fraction, the answer is -51/56

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