Answers

Subtract 81/70 from 70/90

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

70/90 - 81/70 is -239/630.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 70 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 90 × 7 = 630,
   70/90 = 70 × 7/90 × 7 = 490/630
3. Likewise, for the 2nd fraction, since 70 × 9 = 630,
   81/70 = 81 × 9/70 × 9 = 729/630
4. Subtract the two like fractions:
   490/630 - 729/630 = 490 - 729/630 = -239/630

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