Answers

Add 21/42 and 45/4

1^st number: 21/42, 2^nd number: 11 1/4

21/42 + 45/4 is 47/4.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 4 is 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,
   45/4 = 45 × 21/4 × 21 = 945/84
4. Add the two fractions:
   42/84 + 945/84 = 42 + 945/84 = 987/84
5. 987/84 simplified gives 47/4
6. So, 21/42 + 45/4 = 47/4
   In mixed form: 113/4

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