Answers

Add 21/81 and 56/63

21/81 + 56/63 is 31/27.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 63 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 81 × 7 = 567,
   21/81 = 21 × 7/81 × 7 = 147/567
3. Likewise, for the 2nd fraction, since 63 × 9 = 567,
   56/63 = 56 × 9/63 × 9 = 504/567
4. Add the two like fractions:
   147/567 + 504/567 = 147 + 504/567 = 651/567
5. 651/567 simplified gives 31/27
6. So, 21/81 + 56/63 = 31/27
   In mixed form: 14/27

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