Answers

Add 42/90 and 90/81

1^st number: 42/90, 2^nd number: 1 9/81

42/90 + 90/81 is 71/45.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 81 is 810
   
   Next, find the equivalent fraction of both fractional numbers with denominator 810
2. For the 1st fraction, since 90 × 9 = 810,
   42/90 = 42 × 9/90 × 9 = 378/810
3. Likewise, for the 2nd fraction, since 81 × 10 = 810,
   90/81 = 90 × 10/81 × 10 = 900/810
4. Add the two like fractions:
   378/810 + 900/810 = 378 + 900/810 = 1278/810
5. 1278/810 simplified gives 71/45
6. So, 42/90 + 90/81 = 71/45
   In mixed form: 126/45

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