Answers

Add 72/42 and 45/84

1^st number: 1 30/42, 2^nd number: 45/84

72/42 + 45/84 is 9/4.

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,
   72/42 = 72 × 2/42 × 2 = 144/84
3. Likewise, for the 2nd fraction, since 84 × 1 = 84,
   45/84 = 45 × 1/84 × 1 = 45/84
4. Add the two like fractions:
   144/84 + 45/84 = 144 + 45/84 = 189/84
5. 189/84 simplified gives 9/4
6. So, 72/42 + 45/84 = 9/4
   In mixed form: 21/4

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