Answers

Subtract 63/54 from 20/21

1^st number: 20/21, 2^nd number: 1 9/54

20/21 - 63/54 is -3/14.

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,
   20/21 = 20 × 18/21 × 18 = 360/378
3. Likewise, for the 2nd fraction, since 54 × 7 = 378,
   63/54 = 63 × 7/54 × 7 = 441/378
4. Subtract the two like fractions:
   360/378 - 441/378 = 360 - 441/378 = -81/378
5. After reducing the fraction, the answer is -3/14

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