Answers

Subtract 18/7 from 81/20

1^st number: 4 1/20, 2^nd number: 2 4/7

81/20 - 18/7 is 207/140.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 7 is 140
   
   Next, find the equivalent fraction of both fractional numbers with denominator 140
2. For the 1st fraction, since 20 × 7 = 140,
   81/20 = 81 × 7/20 × 7 = 567/140
3. Likewise, for the 2nd fraction, since 7 × 20 = 140,
   18/7 = 18 × 20/7 × 20 = 360/140
4. Subtract the two like fractions:
   567/140 - 360/140 = 567 - 360/140 = 207/140
5. In mixed form: 167/140

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