Answers

Subtract 70/21 from 63/42

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

63/42 - 70/21 is -11/6.

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,
   63/42 = 63 × 1/42 × 1 = 63/42
3. Likewise, for the 2nd fraction, since 21 × 2 = 42,
   70/21 = 70 × 2/21 × 2 = 140/42
4. Subtract the two like fractions:
   63/42 - 140/42 = 63 - 140/42 = -77/42
5. After reducing the fraction, the answer is -11/6

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