Answers

Subtract 45/42 from 20/30

1^st number: 20/30, 2^nd number: 1 3/42

20/30 - 45/42 is -17/42.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 42 is 210
   
   Next, find the equivalent fraction of both fractional numbers with denominator 210
2. For the 1st fraction, since 30 × 7 = 210,
   20/30 = 20 × 7/30 × 7 = 140/210
3. Likewise, for the 2nd fraction, since 42 × 5 = 210,
   45/42 = 45 × 5/42 × 5 = 225/210
4. Subtract the two like fractions:
   140/210 - 225/210 = 140 - 225/210 = -85/210
5. After reducing the fraction, the answer is -17/42

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