Geometry

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Geometry

by RiyaR » Mon Jul 21, 2014 9:21 am
1. Aboy is standing at a distance of 12m infornt of a light pole 16 m high. What is the length of his shadow if the height of the boy is 1m?

2. With the vertices of a traingle as centre, 3 circles are made, each touching the other externally. If the sides of the triangle are 3cm, 6 cm and 7cm respectively, find the radii of the circles in cm.

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by GMATinsight » Mon Jul 21, 2014 10:14 am
RiyaR wrote:1. Aboy is standing at a distance of 12m infornt of a light pole 16 m high. What is the length of his shadow if the height of the boy is 1m?

2. With the vertices of a traingle as centre, 3 circles are made, each touching the other externally. If the sides of the triangle are 3cm, 6 cm and 7cm respectively, find the radii of the circles in cm.
Answer to Question 1:

Concept:
Ratio of Heights of Pole and boy = Ratio of Lengths of shadows of Pole and boy respectively

Something seems missing...
[Considering the boy is standing right at the end of the shadow]


16/12 = 1/x

i.e. x = 4/3 mt. Answer
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by GMATinsight » Mon Jul 21, 2014 10:29 am
RiyaR wrote: 2. With the vertices of a traingle as centre, 3 circles are made, each touching the other externally. If the sides of the triangle are 3cm, 6 cm and 7cm respectively, find the radii of the circles in cm.
Answer to Question 2:

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