Answers

Subtract 63/9 from 27/21

1^st number: 1 6/21, 2^nd number: 7 0/9

27/21 - 63/9 is -40/7.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 9 is 63
   
   Next, find the equivalent fraction of both fractional numbers with denominator 63
2. For the 1st fraction, since 21 × 3 = 63,
   27/21 = 27 × 3/21 × 3 = 81/63
3. Likewise, for the 2nd fraction, since 9 × 7 = 63,
   63/9 = 63 × 7/9 × 7 = 441/63
4. Subtract the two like fractions:
   81/63 - 441/63 = 81 - 441/63 = -360/63
5. After reducing the fraction, the answer is -40/7

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