Answers

Subtract 45/42 from 18/84

1^st number: 18/84, 2^nd number: 1 3/42

18/84 - 45/42 is -6/7.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 42 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 84 × 1 = 84,
   18/84 = 18 × 1/84 × 1 = 18/84
3. Likewise, for the 2nd fraction, since 42 × 2 = 84,
   45/42 = 45 × 2/42 × 2 = 90/84
4. Subtract the two like fractions:
   18/84 - 90/84 = 18 - 90/84 = -72/84
5. After reducing the fraction, the answer is -6/7

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