Answers

Subtract 28/21 from 7/9

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

7/9 - 28/21 is -5/9.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 9 and 21 is 63
   
   Next, find the equivalent fraction of both fractional numbers with denominator 63
2. For the 1st fraction, since 9 × 7 = 63,
   7/9 = 7 × 7/9 × 7 = 49/63
3. Likewise, for the 2nd fraction, since 21 × 3 = 63,
   28/21 = 28 × 3/21 × 3 = 84/63
4. Subtract the two like fractions:
   49/63 - 84/63 = 49 - 84/63 = -35/63
5. After reducing the fraction, the answer is -5/9

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