Answers

Subtract 90/70 from 27/80

1^st number: 27/80, 2^nd number: 1 20/70

27/80 - 90/70 is -531/560.

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,
   27/80 = 27 × 7/80 × 7 = 189/560
3. Likewise, for the 2nd fraction, since 70 × 8 = 560,
   90/70 = 90 × 8/70 × 8 = 720/560
4. Subtract the two like fractions:
   189/560 - 720/560 = 189 - 720/560 = -531/560

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