JEE Main 2021MathematicsProperties of TrianglesEasyNumerical

JEE Main 2021 — Properties of Triangles Question with Solution

JEE Main 2021 (16 Mar Shift 2)

Question

In ΔABC, the lengths of sides AC and AB are 12 cm and 5 cm, respectively. If the area of ∆ABC is 30 cm2 and R and r are respectively the radii of circumcircle and incircle of ΔABC, then the value of 2R+r (in cm) is equal to ______ .

Enter your answer

Show full solutionCorrect answer: 15
Correct answer
15

Step-by-step explanation

Δ=12·5·12·sinA=30

sinA=1

A=90°⇒BC=13

BC=2R=13

r=ΔS=3015=2

2R+r=15

Practice this on the real CBT interface

Solve this JEE Main question (and the rest of the Properties of Triangles chapter) on PrepSharp's TCS iON-style CBT player — with timer, bookmarks and session analytics.

Solve interactively →

About this question

This is a previous-year question from JEE Main 2021, covering the Properties of Triangles chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.