Answers

Add 72/90 and 81/20

1^st number: 72/90, 2^nd number: 4 1/20

72/90 + 81/20 is 97/20.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 20 is 180
   
   Next, find the equivalent fraction of both fractional numbers with denominator 180
2. For the 1st fraction, since 90 × 2 = 180,
   72/90 = 72 × 2/90 × 2 = 144/180
3. Likewise, for the 2nd fraction, since 20 × 9 = 180,
   81/20 = 81 × 9/20 × 9 = 729/180
4. Add the two like fractions:
   144/180 + 729/180 = 144 + 729/180 = 873/180
5. 873/180 simplified gives 97/20
6. So, 72/90 + 81/20 = 97/20
   In mixed form: 417/20

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