PS (Geomtery)
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Let A = the cash register, B = one of the dressing rooms, and C = the other dressing room.A cash register in a certain clothing store is the same distance from two dressing rooms in the store.If the distance between the two dressing rooms is 16 feet, which of the following could be the distance between the cash register and either dressing room?
I 6 feet
II 12 feet
III 24 feet
I only
II only
III only
I and II
II and III
The three points A, B, and C form ∆ABC.
Since the cash register is the same distance from each dressing room, AB = AC.
Since the distance between the dressing rooms is 16 feet, BC = 16.
Thus, ∆ABC is an isosceles triangle, where AB=AC and BC = 16.
The THIRD SIDE of a triangle must be LESS THAN THE SUM of the lengths of the other two sides.
Thus:
BC < AB+AC
16 < AB+AC
AB + AC > 16.
Since AB=AC, we get:
AB + AB > 16
2(AB) > 16
AB > 8.
Of the three options for AB -- 6, 12, and 24 -- only II and III are possible.
The correct answer is E.
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I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
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In addition to this, to verify your answer:
If you are given with 2 sides of a triangle, the length of third side must lie between difference and sum of the given two sides.
Thanks-
Nil
If you are given with 2 sides of a triangle, the length of third side must lie between difference and sum of the given two sides.
Thanks-
Nil
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One easy way to remember this - at least for me - is to visualize a 'triangle' whose sides violate this restriction. Consider a 'triangle' of sides 3, 5, and 9, for instance. You have to somehow connect the three sides to form three vertices, but the 3 and 5 sides are too short to reach opposite ends of the 9 side, leaving you with just a line, and a pretty lousy one at that. (To really get a sense of this, actually cut a few thin pieces of paper with these lengths and see what happens, or just check out https://en.wikipedia.org/wiki/File:Trian ... uality.PNG.)beatthe800 wrote:In addition to this, to verify your answer:
If you are given with 2 sides of a triangle, the length of third side must lie between difference and sum of the given two sides.
Thanks-
Nil