SSC CGL 2025 PYQ — Question 58

SSC CGL - 18 Sep 2025 - Shift 1 • Quantitative Aptitude • Q58

ΔABC has its centroid at point G(4, 5) and vertex A is located at (2, 3). If point D is the midpoint of side BC, what are the coordinates of D?

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Correct answer: A

Explanation

The correct answer is Option 1 i.e. (5, 6).

Centroid G = (4, 5), vertex A = (2, 3), D is midpoint of BC.

The centroid divides the median AD in the ratio of 2 : 1. So, AG : GD = 2 : 1

Using section formula for internal division:

If point G divides AD in ratio m : n with A and D as endpoints, then

G=(m⋅xD+n⋅xAm+n,m⋅yD+n⋅yAm+n)G = \left( \frac{m \cdot x_D + n \cdot x_A}{m + n}, \frac{m \cdot y_D + n \cdot y_A}{m + n} \right)

Here m = AG = 2, n = GD = 1

So, Gx=2⋅xD+1⋅xA3,Gy=2⋅yD+1⋅yA3G_x = \frac{2 \cdot x_D + 1 \cdot x_A}{3}, \quad G_y = \frac{2 \cdot y_D + 1 \cdot y_A}{3}

Substitute G = (4, 5), A = (2, 3): 4=2xD+234 = \frac{2x_D + 2}{3}

⇒ 12=2xD+212 = 2x_D + 2

⇒ 2xD=102x_D = 10

⇒ xD = 5

5=2yD+335 = \frac{2y_D + 3}{3}

⇒ 15=2yD+315 = 2y_D + 3

⇒ 2yD = 12

⇒ yD = 6

So, D = (xD, yD) = (5, 6)