Answers

Add 21/28 and 90/42

1^st number: 21/28, 2^nd number: 2 6/42

21/28 + 90/42 is 81/28.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 28 and 42 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 28 × 3 = 84,
   21/28 = 21 × 3/28 × 3 = 63/84
3. Likewise, for the 2nd fraction, since 42 × 2 = 84,
   90/42 = 90 × 2/42 × 2 = 180/84
4. Add the two like fractions:
   63/84 + 180/84 = 63 + 180/84 = 243/84
5. 243/84 simplified gives 81/28
6. So, 21/28 + 90/42 = 81/28
   In mixed form: 225/28

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