Answers

Add 80/81 and 25/40

80/81 + 25/40 is 1045/648.

Steps for adding 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,
   80/81 = 80 × 40/81 × 40 = 3200/3240
3. Likewise, for the 2nd fraction, since 40 × 81 = 3240,
   25/40 = 25 × 81/40 × 81 = 2025/3240
4. Add the two like fractions:
   3200/3240 + 2025/3240 = 3200 + 2025/3240 = 5225/3240
5. 5225/3240 simplified gives 1045/648
6. So, 80/81 + 25/40 = 1045/648
   In mixed form: 1397/648

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