Answers

Add 72/18 and 45/21

1^st number: 4 0/18, 2^nd number: 2 3/21

72/18 + 45/21 is 43/7.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 21 is 126
   
   Next, find the equivalent fraction of both fractional numbers with denominator 126
2. For the 1st fraction, since 18 × 7 = 126,
   72/18 = 72 × 7/18 × 7 = 504/126
3. Likewise, for the 2nd fraction, since 21 × 6 = 126,
   45/21 = 45 × 6/21 × 6 = 270/126
4. Add the two like fractions:
   504/126 + 270/126 = 504 + 270/126 = 774/126
5. 774/126 simplified gives 43/7
6. So, 72/18 + 45/21 = 43/7
   In mixed form: 61/7

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