Answers

Subtract 40/42 from 81/30

1^st number: 2 21/30, 2^nd number: 40/42

81/30 - 40/42 is 367/210.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 42 is 210
   
   Next, find the equivalent fraction of both fractional numbers with denominator 210
2. For the 1st fraction, since 30 × 7 = 210,
   81/30 = 81 × 7/30 × 7 = 567/210
3. Likewise, for the 2nd fraction, since 42 × 5 = 210,
   40/42 = 40 × 5/42 × 5 = 200/210
4. Subtract the two like fractions:
   567/210 - 200/210 = 567 - 200/210 = 367/210
5. In mixed form: 1157/210

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