Explanation
1. Pascal's Identity Formula:
(kN)+(k−1N)=(kN+1)
This rule states that adding two combinations with the same upper index (N) and consecutive lower indices (k and k−1) equals a combination where the upper index increases by 1 and the lower index takes the larger of the two values (k).
2. Compare with the Given Equation:
The equation given in the problem is:
(815)+(715)=(rn)
By mapping our problem to Pascal's Identity, we can identify:
3. Calculate the Values of n and r:
Applying the formula:
(815)+(715)=(815+1)
(815)+(715)=(816)
Now, compare (816) with the right-hand side of the given question, (rn):
Conclusion
The values of n and r are 16 and 8 respectively.
Therefore, the correct option is B) 16 and 8.