Q178 / 270 · NDA 2016 (Phase 1) · Mathematics
Consider the lines $y=3 x, y=6 x$ and $y=9$.
The centroid of the triangle is at which one of the following points?
- A$(3,6)$
- Correct answerB$\left(\frac{3}{2}, 6\right)$
- C$(3,3)$
- D$\left(\frac{3}{2}, 9\right)$
Solution
Coordinates of $O, A, B$ are $(0,0)\left(\frac{3}{2}, 9\right),(3,9)$ respectively.
$\therefore$ Centroid $C=\left[\left(\frac{0+\frac{3}{2}+3}{3}\right),\left(\frac{0+9+9}{3}\right)\right]=\left(\frac{3}{2}, 6\right)$
Hence, the correct answer is option: 'B'.