Answers

Add 18/21 and 54/45

1^st number: 18/21, 2^nd number: 1 9/45

18/21 + 54/45 is 72/35.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 45 is 315
   
   Next, find the equivalent fraction of both fractional numbers with denominator 315
2. For the 1st fraction, since 21 × 15 = 315,
   18/21 = 18 × 15/21 × 15 = 270/315
3. Likewise, for the 2nd fraction, since 45 × 7 = 315,
   54/45 = 54 × 7/45 × 7 = 378/315
4. Add the two like fractions:
   270/315 + 378/315 = 270 + 378/315 = 648/315
5. 648/315 simplified gives 72/35
6. So, 18/21 + 54/45 = 72/35
   In mixed form: 22/35

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