Answers

Subtract 90/70 from 30/90

1^st number: 30/90, 2^nd number: 1 20/70

30/90 - 90/70 is -20/21.

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,
   30/90 = 30 × 7/90 × 7 = 210/630
3. Likewise, for the 2nd fraction, since 70 × 9 = 630,
   90/70 = 90 × 9/70 × 9 = 810/630
4. Subtract the two like fractions:
   210/630 - 810/630 = 210 - 810/630 = -600/630
5. After reducing the fraction, the answer is -20/21

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