Answers

Subtract 42/54 from 40/21

1^st number: 1 19/21, 2^nd number: 42/54

40/21 - 42/54 is 71/63.

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,
   40/21 = 40 × 18/21 × 18 = 720/378
3. Likewise, for the 2nd fraction, since 54 × 7 = 378,
   42/54 = 42 × 7/54 × 7 = 294/378
4. Subtract the two like fractions:
   720/378 - 294/378 = 720 - 294/378 = 426/378
5. After reducing the fraction, the answer is 71/63
6. In mixed form: 18/63

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