Answers

Subtract 30/4 from 21/42

1^st number: 21/42, 2^nd number: 7 2/4

21/42 - 30/4 is -7/1.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 4 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 42 × 2 = 84,
   21/42 = 21 × 2/42 × 2 = 42/84
3. Likewise, for the 2nd fraction, since 4 × 21 = 84,
   30/4 = 30 × 21/4 × 21 = 630/84
4. Subtract the two like fractions:
   42/84 - 630/84 = 42 - 630/84 = -588/84
5. After reducing the fraction, the answer is -7/1

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