IIFT 2019 Question Paper | Quants

CAT Questions

The best way to boost your IIFT prep is to practice the actual IIFT Question Papers. 2IIM offers you exactly that, in a student friendly format to take value from this. In the 2019 IIFT, quants were a mixed bag of questions of varying difficulty, with some routine questions and the others were very demanding. Some beautiful questions that laid emphasis on Learning ideas from basics and being able to comprehend more than remembering gazillion formulae and shortcuts.

Question 13: In a triangle, the two longest sides are 13 cm and 12 cm. The angles of the triangle are in arithmetic progression. The radius of the circle inscribed in this triangle is :

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Video Explanation

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Explanatory Answer

Let the triangle be ABC
Let AB = 13 cm and BC = 12 cm and CA be x
Since the angles are in AP, let the angles be a-d , a , a+d
Sum of three angles =180 degree
Hence a = 60 degree

Using Cosine Rule:
cos 60 = \\frac{(13^2 + x^2 – 12^2)}{2 × 13 × x})
Solving this we get x = 10.65 or 2.34
Area/semi-perimeter = in-radius
Area =\\frac{1}{2}) × 13x sin 60
Putting two values of x we get in radius as 3.36 or 1
Only 1 can be the inradius among 1 and 3.36
Hence, the answer is, "1"

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The question is "The radius of the circle inscribed in this triangle is :"

Hence, the answer is, "1"