Answers

Add 5/21 and 21/63

5/21 + 21/63 is 4/7.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 63 is 63
   
   Next, find the equivalent fraction of both fractional numbers with denominator 63
2. For the 1st fraction, since 21 × 3 = 63,
   5/21 = 5 × 3/21 × 3 = 15/63
3. Likewise, for the 2nd fraction, since 63 × 1 = 63,
   21/63 = 21 × 1/63 × 1 = 21/63
4. Add the two like fractions:
   15/63 + 21/63 = 15 + 21/63 = 36/63
5. 36/63 simplified gives 4/7
6. So, 5/21 + 21/63 = 4/7

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