Answers

Subtract 45/7 from 21/42

1^st number: 21/42, 2^nd number: 6 3/7

21/42 - 45/7 is -83/14.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 7 is 42
   
   Next, find the equivalent fraction of both fractional numbers with denominator 42
2. For the 1st fraction, since 42 × 1 = 42,
   21/42 = 21 × 1/42 × 1 = 21/42
3. Likewise, for the 2nd fraction, since 7 × 6 = 42,
   45/7 = 45 × 6/7 × 6 = 270/42
4. Subtract the two like fractions:
   21/42 - 270/42 = 21 - 270/42 = -249/42
5. After reducing the fraction, the answer is -83/14

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