Answers

Add 15/60 and 21/63

15/60 + 21/63 is 7/12.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 60 and 63 is 1260
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1260
2. For the 1st fraction, since 60 × 21 = 1260,
   15/60 = 15 × 21/60 × 21 = 315/1260
3. Likewise, for the 2nd fraction, since 63 × 20 = 1260,
   21/63 = 21 × 20/63 × 20 = 420/1260
4. Add the two like fractions:
   315/1260 + 420/1260 = 315 + 420/1260 = 735/1260
5. 735/1260 simplified gives 7/12
6. So, 15/60 + 21/63 = 7/12

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