Answers

Add 12/40 and 90/81

1^st number: 12/40, 2^nd number: 1 9/81

12/40 + 90/81 is 127/90.

Steps for adding 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,
   12/40 = 12 × 81/40 × 81 = 972/3240
3. Likewise, for the 2nd fraction, since 81 × 40 = 3240,
   90/81 = 90 × 40/81 × 40 = 3600/3240
4. Add the two like fractions:
   972/3240 + 3600/3240 = 972 + 3600/3240 = 4572/3240
5. 4572/3240 simplified gives 127/90
6. So, 12/40 + 90/81 = 127/90
   In mixed form: 137/90

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