Answers

Add 21/4 and 20/81

1^st number: 5 1/4, 2^nd number: 20/81

21/4 + 20/81 is 1781/324.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 4 and 81 is 324
   
   Next, find the equivalent fraction of both fractional numbers with denominator 324
2. For the 1st fraction, since 4 × 81 = 324,
   21/4 = 21 × 81/4 × 81 = 1701/324
3. Likewise, for the 2nd fraction, since 81 × 4 = 324,
   20/81 = 20 × 4/81 × 4 = 80/324
4. Add the two like fractions:
   1701/324 + 80/324 = 1701 + 80/324 = 1781/324
5. So, 21/4 + 20/81 = 1781/324
   In mixed form: 5161/324

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