Answers

Subtract 81/80 from 30/36

1^st number: 30/36, 2^nd number: 1 1/80

30/36 - 81/80 is -43/240.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 36 and 80 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 36 × 20 = 720,
   30/36 = 30 × 20/36 × 20 = 600/720
3. Likewise, for the 2nd fraction, since 80 × 9 = 720,
   81/80 = 81 × 9/80 × 9 = 729/720
4. Subtract the two like fractions:
   600/720 - 729/720 = 600 - 729/720 = -129/720
5. After reducing the fraction, the answer is -43/240

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