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If the Angles of a Triangle Are in the Ratio 2 : 1 : 3, Then Find the Measure of Smallest Angle.

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Question

If the angles of a triangle are in the ratio 2 : 1 : 3, then find the measure of smallest angle.

Answer in Brief
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Solution

In the given problem, angles of ΔABC are in the ratio 2:1:3

We need to find the measure of the smallest angle.

Let,

∠A = 2x

∠B = x

∠C = 3x

According to the angle sum property of the triangle, in ΔABC, we get,

2x + 1x + 3x = 180°

               6x = 180°

                `x = (180°)/6`

                 x = 30°

Thus, 

∠A - 2(30°) = 60

∠B = 1(30°) = 30

∠C = 3(30°) = 90°

Since, the measure of  ∠Bis the smallest of all the three angles.

Therefore, the measure of the smallest angle is 30°.

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Chapter 11: Triangle and its Angles - Exercise 11.3 [Page 23]

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R.D. Sharma Mathematics [English] Class 9
Chapter 11 Triangle and its Angles
Exercise 11.3 | Q 4 | Page 23

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