Answers

Subtract 21/45 from 81/80

1^st number: 1 1/80, 2^nd number: 21/45

81/80 - 21/45 is 131/240.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 45 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 80 × 9 = 720,
   81/80 = 81 × 9/80 × 9 = 729/720
3. Likewise, for the 2nd fraction, since 45 × 16 = 720,
   21/45 = 21 × 16/45 × 16 = 336/720
4. Subtract the two like fractions:
   729/720 - 336/720 = 729 - 336/720 = 393/720
5. After reducing the fraction, the answer is 131/240

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