Answers

Subtract 28/90 from 15/70

15/70 - 28/90 is -61/630.

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,
   15/70 = 15 × 9/70 × 9 = 135/630
3. Likewise, for the 2nd fraction, since 90 × 7 = 630,
   28/90 = 28 × 7/90 × 7 = 196/630
4. Subtract the two like fractions:
   135/630 - 196/630 = 135 - 196/630 = -61/630

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