Answers

Subtract 72/70 from 3/90

1^st number: 3/90, 2^nd number: 1 2/70

3/90 - 72/70 is -209/210.

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,
   3/90 = 3 × 7/90 × 7 = 21/630
3. Likewise, for the 2nd fraction, since 70 × 9 = 630,
   72/70 = 72 × 9/70 × 9 = 648/630
4. Subtract the two like fractions:
   21/630 - 648/630 = 21 - 648/630 = -627/630
5. After reducing the fraction, the answer is -209/210

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