Answers

Add 90/20 and 20/81

1^st number: 4 10/20, 2^nd number: 20/81

90/20 + 20/81 is 769/162.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 81 is 1620
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1620
2. For the 1st fraction, since 20 × 81 = 1620,
   90/20 = 90 × 81/20 × 81 = 7290/1620
3. Likewise, for the 2nd fraction, since 81 × 20 = 1620,
   20/81 = 20 × 20/81 × 20 = 400/1620
4. Add the two like fractions:
   7290/1620 + 400/1620 = 7290 + 400/1620 = 7690/1620
5. 7690/1620 simplified gives 769/162
6. So, 90/20 + 20/81 = 769/162
   In mixed form: 4121/162

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