Answers

Subtract 45/42 from 28/90

1^st number: 28/90, 2^nd number: 1 3/42

28/90 - 45/42 is -479/630.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 42 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 90 × 7 = 630,
   28/90 = 28 × 7/90 × 7 = 196/630
3. Likewise, for the 2nd fraction, since 42 × 15 = 630,
   45/42 = 45 × 15/42 × 15 = 675/630
4. Subtract the two like fractions:
   196/630 - 675/630 = 196 - 675/630 = -479/630

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