Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Mensuration: 2D

Question:

The sum of radius of circles is 119 cm and the difference between their area is 17204 sq. cm.  What is the radius (in cm) of the larger circle?

Options:

36.5

46

64.25

82.5

Correct Answer:

82.5

Explanation:

Sum of radius = r1 + r2 = 119                (r1 > r2

Difference in area = π r12 - π r22

                 17204 = π (r1 - r2) (r1 + r2)

                 17204 = \(\frac{22}{7}\) × 119 × (r1 - r2)

⇒ (r1 - r2) = 46

⇒ (r1 + r2) = 119

Adding both, we get

⇒ 2 r1 = 165

⇒    r1 = 82.5