Answers

Subtract 8/30 from 81/42

1^st number: 1 39/42, 2^nd number: 8/30

81/42 - 8/30 is 349/210.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 30 is 210
   
   Next, find the equivalent fraction of both fractional numbers with denominator 210
2. For the 1st fraction, since 42 × 5 = 210,
   81/42 = 81 × 5/42 × 5 = 405/210
3. Likewise, for the 2nd fraction, since 30 × 7 = 210,
   8/30 = 8 × 7/30 × 7 = 56/210
4. Subtract the two like fractions:
   405/210 - 56/210 = 405 - 56/210 = 349/210
5. In mixed form: 1139/210

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