Answers

Add 7/21 and 42/81

7/21 + 42/81 is 23/27.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 81 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 21 × 27 = 567,
   7/21 = 7 × 27/21 × 27 = 189/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   42/81 = 42 × 7/81 × 7 = 294/567
4. Add the two like fractions:
   189/567 + 294/567 = 189 + 294/567 = 483/567
5. 483/567 simplified gives 23/27
6. So, 7/21 + 42/81 = 23/27

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