Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Mensuration: 3D

Question:

The sides of a triangle are 24 cm, 26 cm and 10 cm. At each of its vertices, circles of radius 4.2 cm are drawn. What is the area (in cm2) of the triangle, excluding the portion covered by the sectors of the circles? $(\pi=\frac{22}{7})$

Options:

120

105.86

92.28

27.72

Correct Answer:

92.28

Explanation:

We have a concept,

The area made by three circles in three vertices of a triangle of the same radius will be half the area of the circle.

We have given,

The sides of the triangle = 24 cm, 26 cm, and 10 cm.

The radius of the circle in three vertices = 4.2 cm

As the triangle is a right angled triangle,

Area of the triangle = \(\frac{1}{2}\) × 24 × 10 = 120 cm2

The total angle created in three circles in the vertices = 180° 

The area of the triangle which is inside the common portion of the triangle and circle = \(\frac{1}{2}\) × \(\frac{22}{7}\) ×  (4.2)2 = 27.72 cm2

The required area =  (120 - 27.72) = 92.28 cm2