Answers

Subtract 10/21 from 81/30

1^st number: 2 21/30, 2^nd number: 10/21

81/30 - 10/21 is 467/210.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 21 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 21 × 10 = 210,
   10/21 = 10 × 10/21 × 10 = 100/210
4. Subtract the two like fractions:
   567/210 - 100/210 = 567 - 100/210 = 467/210
5. In mixed form: 247/210

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