Answers

Subtract 90/40 from 1/81

1^st number: 1/81, 2^nd number: 2 10/40

1/81 - 90/40 is -725/324.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 40 is 3240
   
   Next, find the equivalent fraction of both fractional numbers with denominator 3240
2. For the 1st fraction, since 81 × 40 = 3240,
   1/81 = 1 × 40/81 × 40 = 40/3240
3. Likewise, for the 2nd fraction, since 40 × 81 = 3240,
   90/40 = 90 × 81/40 × 81 = 7290/3240
4. Subtract the two like fractions:
   40/3240 - 7290/3240 = 40 - 7290/3240 = -7250/3240
5. After reducing the fraction, the answer is -725/324

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