Answers

Add 21/42 and 90/84

1^st number: 21/42, 2^nd number: 1 6/84

21/42 + 90/84 is 11/7.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 84 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 84 × 1 = 84,
   90/84 = 90 × 1/84 × 1 = 90/84
4. Add the two like fractions:
   42/84 + 90/84 = 42 + 90/84 = 132/84
5. 132/84 simplified gives 11/7
6. So, 21/42 + 90/84 = 11/7
   In mixed form: 14/7

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