Question

If P(n, 5) = 20P (n, 3), then n =

• A. 2
• B. 4
• C. 6
• D. 8

Answer 1

The correct option is D 8

$P(n,5)=20P(n,3)\Rightarrow \frac{\angle n}{\angle n-5}=\frac{20\angle n}{\angle n-3}$ $\Rightarrow (n-3)(n-4)=5\times 4$ $\Rightarrow n-3=5\Rightarrow n=8$