Answers

Add 72/20 and 81/70

1^st number: 3 12/20, 2^nd number: 1 11/70

72/20 + 81/70 is 333/70.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 70 is 140
   
   Next, find the equivalent fraction of both fractional numbers with denominator 140
2. For the 1st fraction, since 20 × 7 = 140,
   72/20 = 72 × 7/20 × 7 = 504/140
3. Likewise, for the 2nd fraction, since 70 × 2 = 140,
   81/70 = 81 × 2/70 × 2 = 162/140
4. Add the two like fractions:
   504/140 + 162/140 = 504 + 162/140 = 666/140
5. 666/140 simplified gives 333/70
6. So, 72/20 + 81/70 = 333/70
   In mixed form: 453/70

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