Answers

Subtract 45/21 from 1/42

1^st number: 1/42, 2^nd number: 2 3/21

1/42 - 45/21 is -89/42.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 21 is 42
   
   Next, find the equivalent fraction of both fractional numbers with denominator 42
2. For the 1st fraction, since 42 × 1 = 42,
   1/42 = 1 × 1/42 × 1 = 1/42
3. Likewise, for the 2nd fraction, since 21 × 2 = 42,
   45/21 = 45 × 2/21 × 2 = 90/42
4. Subtract the two like fractions:
   1/42 - 90/42 = 1 - 90/42 = -89/42

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