Answers

Add 18/21 and 54/8

1^st number: 18/21, 2^nd number: 6 6/8

18/21 + 54/8 is 213/28.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 8 is 168
   
   Next, find the equivalent fraction of both fractional numbers with denominator 168
2. For the 1st fraction, since 21 × 8 = 168,
   18/21 = 18 × 8/21 × 8 = 144/168
3. Likewise, for the 2nd fraction, since 8 × 21 = 168,
   54/8 = 54 × 21/8 × 21 = 1134/168
4. Add the two like fractions:
   144/168 + 1134/168 = 144 + 1134/168 = 1278/168
5. 1278/168 simplified gives 213/28
6. So, 18/21 + 54/8 = 213/28
   In mixed form: 717/28

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