Answers

Subtract 56/81 from 42/40

1^st number: 1 2/40, 2^nd number: 56/81

42/40 - 56/81 is 581/1620.

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,
   56/81 = 56 × 40/81 × 40 = 2240/3240
4. Subtract the two like fractions:
   3402/3240 - 2240/3240 = 3402 - 2240/3240 = 1162/3240
5. After reducing the fraction, the answer is 581/1620

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