Answers

Subtract 80/90 from 81/70

1^st number: 1 11/70, 2^nd number: 80/90

81/70 - 80/90 is 169/630.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 70 and 90 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 70 × 9 = 630,
   81/70 = 81 × 9/70 × 9 = 729/630
3. Likewise, for the 2nd fraction, since 90 × 7 = 630,
   80/90 = 80 × 7/90 × 7 = 560/630
4. Subtract the two like fractions:
   729/630 - 560/630 = 729 - 560/630 = 169/630

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