Answers

Subtract 40/42 from 81/18

1^st number: 4 9/18, 2^nd number: 40/42

81/18 - 40/42 is 149/42.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 42 is 126
   
   Next, find the equivalent fraction of both fractional numbers with denominator 126
2. For the 1st fraction, since 18 × 7 = 126,
   81/18 = 81 × 7/18 × 7 = 567/126
3. Likewise, for the 2nd fraction, since 42 × 3 = 126,
   40/42 = 40 × 3/42 × 3 = 120/126
4. Subtract the two like fractions:
   567/126 - 120/126 = 567 - 120/126 = 447/126
5. After reducing the fraction, the answer is 149/42
6. In mixed form: 323/42

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