Answers

Subtract 9/7 from 21/63

1^st number: 21/63, 2^nd number: 1 2/7

21/63 - 9/7 is -20/21.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 63 and 7 is 63
   
   Next, find the equivalent fraction of both fractional numbers with denominator 63
2. For the 1st fraction, since 63 × 1 = 63,
   21/63 = 21 × 1/63 × 1 = 21/63
3. Likewise, for the 2nd fraction, since 7 × 9 = 63,
   9/7 = 9 × 9/7 × 9 = 81/63
4. Subtract the two like fractions:
   21/63 - 81/63 = 21 - 81/63 = -60/63
5. After reducing the fraction, the answer is -20/21

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