In $\triangle P Q R, M$ is the mid-point of $Q R$ and $C$ is the mid-point of $P M$. If $Q C$ when extended…

In $\triangle P Q R, M$ is the mid-point of $Q R$ and $C$ is the mid-point of $P M$. If $Q C$ when extended meets $P R$ at $N$, then $\frac{|\overrightarrow{Q N}|}{|\overline{C N}|}=$
  1. 1
  2. 2
  3. 3
  4. 4

Solution

We have, $M$ is the mid-point of $Q R$. $C$ is the mid-point of $P M$. Draw $M O$ such that $M O$ is parallel to $C N$. $\because N$ is the mid-point of $P O$ $ \therefore \quad C N=\frac{1}{2} M O $ $M$ is the mid-point of $Q R$ $\therefore M O$ is parallel to $Q N$ $ \begin{array}{rlrl} \because & & M O & =\frac{1}{2} Q N \\ & \therefore & C N & =\frac{1}{2}\left(\frac{1}{2} Q N\right) C N=\frac{1}{4} Q N \\ \therefore & & \left|\frac{\mathbf{Q N}}{\mathbf{C N}}\right|=4 . \end{array} $

Asked in: AP EAMCET 2018 (22 Apr Shift 1)

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