Answers

Add 40/63 and 21/81

40/63 + 21/81 is 169/189.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 63 and 81 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 63 × 9 = 567,
   40/63 = 40 × 9/63 × 9 = 360/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   21/81 = 21 × 7/81 × 7 = 147/567
4. Add the two like fractions:
   360/567 + 147/567 = 360 + 147/567 = 507/567
5. 507/567 simplified gives 169/189
6. So, 40/63 + 21/81 = 169/189

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