Answers

Add 72/20 and 30/80

1^st number: 3 12/20, 2^nd number: 30/80

72/20 + 30/80 is 159/40.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 80 is 80
   
   Next, find the equivalent fraction of both fractional numbers with denominator 80
2. For the 1st fraction, since 20 × 4 = 80,
   72/20 = 72 × 4/20 × 4 = 288/80
3. Likewise, for the 2nd fraction, since 80 × 1 = 80,
   30/80 = 30 × 1/80 × 1 = 30/80
4. Add the two like fractions:
   288/80 + 30/80 = 288 + 30/80 = 318/80
5. 318/80 simplified gives 159/40
6. So, 72/20 + 30/80 = 159/40
   In mixed form: 339/40

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