Answers

Add 3/21 and 63/84

3/21 + 63/84 is 25/28.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 84 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 21 × 4 = 84,
   3/21 = 3 × 4/21 × 4 = 12/84
3. Likewise, for the 2nd fraction, since 84 × 1 = 84,
   63/84 = 63 × 1/84 × 1 = 63/84
4. Add the two like fractions:
   12/84 + 63/84 = 12 + 63/84 = 75/84
5. 75/84 simplified gives 25/28
6. So, 3/21 + 63/84 = 25/28

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