SSC GD 2021 PYQ — Question 51

SSC GD Constable (English) - 2nd December 2021 Shift 3 • Quantitative Aptitude • Q51

The area of a triangular field with sides 220 m, 231 m and 319 m is equal to 15 times the area of a circular garden. What is the diameter (in m) of a circular garden?

Show answer & explanation

Correct answer: C

Explanation

The correct answer is option 3 i.e. 14√11.

Given:

The area of a triangular field with sides 220 m, 231 m and 319 m = 15 times the area of a circular garden

Formula used:

Area of a right angled triangle = (1/2) × base × height

Area of circle = πr2

Where, r = radius

Calculations:

The sides of the triangle follow the Pythagoras theorem such that we have

Base = 220 m, Height = 231 and Hypotenuse = 319 m

(Hypotenuse)2 = (Base)2 + (Perpendicular)2

(319)2 = (220)2 + (231)2

According to the question,

⇒ Area of triangle = 15 × πr2

⇒ (1/2) × 220 × 231 = 15 × (22/7) × r2

⇒ r2 = 7 × 7 × 11

⇒ r = 7√11

We know that Diameter = 2 × radius

⇒ Diameter = 2 × 7√11 = 14√11