If \( 15\\ 8 + 15\\ 7 = n\\ r \)

then the values..." - Step-by-step solution, answer key, and detailed explanation on MCA Prep."> \( 15\\... - Solved | MCA Prep" /> If \( 15\\ 8 + 15\\ 7 = n\\ r \)

then the values..." - Step-by-step solution, answer key, and detailed explanation on MCA Prep." /> \( 15\\... - Solved | MCA Prep" /> If \( 15\\ 8 + 15\\ 7 = n\\ r \)

then the values..." - Step-by-step solution, answer key, and detailed explanation on MCA Prep." />

Question 1

Mathematics Permutation and Combination Hard

<p>If&nbsp;<span class="math-tex">\(\rm \begin{pmatrix} 15\\ 8\end{pmatrix}+\begin{pmatrix} 15\\ 7\end{pmatrix}=\begin{pmatrix} \rm n\\ \rm r\end{pmatrix}\)</span></p> <p>then the values of n and r are:</p> <p>Where,&nbsp;<span class="math-tex">\(\begin{pmatrix} \rm n\\ \rm r\end{pmatrix} = {}^nC_r\)</span></p>

(A) 16 and 7.
(B) 16 and 8.
(C) 16 and 9.
(D) 30 and 15.
✓ Correct Answer: Option B Verified Solution

📘 Step-by-Step Solution & Detailed Explanation:

The given equation is: \[ \binom{15}{8} + \binom{15}{7} = \binom{n}{r} \] We need to find the values of \(n\) and \(r\). \[\] Simplify the left-hand side We can apply Pascal's identity, which states: \[ \binom{n}{k} + \binom{n}{k+1} = \binom{n+1}{k+1} \] In our case, we have: \[ \binom{15}{8} + \binom{15}{7} = \binom{16}{8} \] [\]\ Express the equation Now, we have the equation: \[ \binom{16}{8} = \binom{n}{r} \] Determine \(n\) and \(r\) From this, we can conclude that: \[ n = 16, \quad r = 8 \] Thus, the values of \(n\) and \(r\) are: \[ n = 16, \quad r = 8 \]

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