Answers

Subtract 27/21 from 42/54

1^st number: 42/54, 2^nd number: 1 6/21

42/54 - 27/21 is -32/63.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 54 and 21 is 378
   
   Next, find the equivalent fraction of both fractional numbers with denominator 378
2. For the 1st fraction, since 54 × 7 = 378,
   42/54 = 42 × 7/54 × 7 = 294/378
3. Likewise, for the 2nd fraction, since 21 × 18 = 378,
   27/21 = 27 × 18/21 × 18 = 486/378
4. Subtract the two like fractions:
   294/378 - 486/378 = 294 - 486/378 = -192/378
5. After reducing the fraction, the answer is -32/63

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