Answers

Subtract 1/24 from 81/21

1^st number: 3 18/21, 2^nd number: 1/24

81/21 - 1/24 is 641/168.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 24 is 168
   
   Next, find the equivalent fraction of both fractional numbers with denominator 168
2. For the 1st fraction, since 21 × 8 = 168,
   81/21 = 81 × 8/21 × 8 = 648/168
3. Likewise, for the 2nd fraction, since 24 × 7 = 168,
   1/24 = 1 × 7/24 × 7 = 7/168
4. Subtract the two like fractions:
   648/168 - 7/168 = 648 - 7/168 = 641/168
5. In mixed form: 3137/168

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