Answers

Add 21/56 and 15/63

21/56 + 15/63 is 103/168.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 56 and 63 is 504
   
   Next, find the equivalent fraction of both fractional numbers with denominator 504
2. For the 1st fraction, since 56 × 9 = 504,
   21/56 = 21 × 9/56 × 9 = 189/504
3. Likewise, for the 2nd fraction, since 63 × 8 = 504,
   15/63 = 15 × 8/63 × 8 = 120/504
4. Add the two like fractions:
   189/504 + 120/504 = 189 + 120/504 = 309/504
5. 309/504 simplified gives 103/168
6. So, 21/56 + 15/63 = 103/168

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