Answers

Add 21/42 and 81/4

1^st number: 21/42, 2^nd number: 20 1/4

21/42 + 81/4 is 83/4.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 4 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 42 × 2 = 84,
   21/42 = 21 × 2/42 × 2 = 42/84
3. Likewise, for the 2nd fraction, since 4 × 21 = 84,
   81/4 = 81 × 21/4 × 21 = 1701/84
4. Add the two like fractions:
   42/84 + 1701/84 = 42 + 1701/84 = 1743/84
5. 1743/84 simplified gives 83/4
6. So, 21/42 + 81/4 = 83/4
   In mixed form: 203/4

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