Answers

Add 30/40 and 81/72

1^st number: 30/40, 2^nd number: 1 9/72

30/40 + 81/72 is 15/8.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 72 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 40 × 9 = 360,
   30/40 = 30 × 9/40 × 9 = 270/360
3. Likewise, for the 2nd fraction, since 72 × 5 = 360,
   81/72 = 81 × 5/72 × 5 = 405/360
4. Add the two like fractions:
   270/360 + 405/360 = 270 + 405/360 = 675/360
5. 675/360 simplified gives 15/8
6. So, 30/40 + 81/72 = 15/8
   In mixed form: 17/8

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