Answers

Subtract 7/81 from 45/40

1^st number: 1 5/40, 2^nd number: 7/81

45/40 - 7/81 is 673/648.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 81 is 3240
   
   Next, find the equivalent fraction of both fractional numbers with denominator 3240
2. For the 1st fraction, since 40 × 81 = 3240,
   45/40 = 45 × 81/40 × 81 = 3645/3240
3. Likewise, for the 2nd fraction, since 81 × 40 = 3240,
   7/81 = 7 × 40/81 × 40 = 280/3240
4. Subtract the two like fractions:
   3645/3240 - 280/3240 = 3645 - 280/3240 = 3365/3240
5. After reducing the fraction, the answer is 673/648
6. In mixed form: 125/648

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