Answers

Add 81/20 and 72/35

1^st number: 4 1/20, 2^nd number: 2 2/35

81/20 + 72/35 is 171/28.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 35 is 140
   
   Next, find the equivalent fraction of both fractional numbers with denominator 140
2. For the 1st fraction, since 20 × 7 = 140,
   81/20 = 81 × 7/20 × 7 = 567/140
3. Likewise, for the 2nd fraction, since 35 × 4 = 140,
   72/35 = 72 × 4/35 × 4 = 288/140
4. Add the two like fractions:
   567/140 + 288/140 = 567 + 288/140 = 855/140
5. 855/140 simplified gives 171/28
6. So, 81/20 + 72/35 = 171/28
   In mixed form: 63/28

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