Answers

Subtract 8/81 from 42/40

1^st number: 1 2/40, 2^nd number: 8/81

42/40 - 8/81 is 1541/1620.

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,
   42/40 = 42 × 81/40 × 81 = 3402/3240
3. Likewise, for the 2nd fraction, since 81 × 40 = 3240,
   8/81 = 8 × 40/81 × 40 = 320/3240
4. Subtract the two like fractions:
   3402/3240 - 320/3240 = 3402 - 320/3240 = 3082/3240
5. After reducing the fraction, the answer is 1541/1620

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