Answers

Add 21/30 and 81/72

1^st number: 21/30, 2^nd number: 1 9/72

21/30 + 81/72 is 73/40.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 72 is 360
   
   Next, find the equivalent fraction of both fractional numbers with denominator 360
2. For the 1st fraction, since 30 × 12 = 360,
   21/30 = 21 × 12/30 × 12 = 252/360
3. Likewise, for the 2nd fraction, since 72 × 5 = 360,
   81/72 = 81 × 5/72 × 5 = 405/360
4. Add the two like fractions:
   252/360 + 405/360 = 252 + 405/360 = 657/360
5. 657/360 simplified gives 73/40
6. So, 21/30 + 81/72 = 73/40
   In mixed form: 133/40

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