Answers

Subtract 21/54 from 28/21

1^st number: 1 7/21, 2^nd number: 21/54

28/21 - 21/54 is 17/18.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 54 is 378
   
   Next, find the equivalent fraction of both fractional numbers with denominator 378
2. For the 1st fraction, since 21 × 18 = 378,
   28/21 = 28 × 18/21 × 18 = 504/378
3. Likewise, for the 2nd fraction, since 54 × 7 = 378,
   21/54 = 21 × 7/54 × 7 = 147/378
4. Subtract the two like fractions:
   504/378 - 147/378 = 504 - 147/378 = 357/378
5. After reducing the fraction, the answer is 17/18

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