If two sides of a triangle have lengths 2 and 5, which of the following could be the perimeter?
I. 9
II. 15
III. 19
A) None
B) I only
C) II only
D) II and III only
E) I, II, and III
OA: A
Please explain...
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Two sides of triangle given, what's possible perimeter?
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phoenixhazard
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The 3rd side of a triangle has to be less than the sum of the other two sides, and more than their difference.
So in our case the 3rd side is 3< s < 7
Perimeter = 2+5+s
assume s = 3 perimeter = 10
assume s = 7 perimeter = 14
So none of the given answers work out as the perimeter has to be > 10 and < 14
So in our case the 3rd side is 3< s < 7
Perimeter = 2+5+s
assume s = 3 perimeter = 10
assume s = 7 perimeter = 14
So none of the given answers work out as the perimeter has to be > 10 and < 14
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GMATGuruNY
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The third side rule of triangles:phoenixhazard wrote:If two sides of a triangle have lengths 2 and 5, which of the following could be the perimeter?
I. 9
II. 15
III. 19
A) None
B) I only
C) II only
D) II and III only
E) I, II, and III
OA: A
Please explain...
The third side of a triangle must be less than the sum of the other 2 sides and bigger than the difference of the other 2 sides.
Thus, given a side of 2, a side of 5, and a third side s:
5-2 < s < 5+2
3 < s < 7.
Let p = perimeter.
If s=3, p = 3+2+5 = 10.
If s=7, p = 7+2+5 = 14.
The values above give the range of the perimeter. Since 3 < s < 7, we know that 10 < p < 14.
Since none of the given perimeters are between 10 and 14, the correct answer is A.
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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.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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phoenixhazard
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goyalsau
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It is a very important rule in the case of Triangles,N:Dure wrote:The 3rd side of a triangle has to be less than the sum of the other two sides, and more than their difference.
Thanks for posting the rule, I almost forgot.......
Saurabh Goyal
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maddy2u
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GMATGuruNY wrote:The third side rule of triangles:phoenixhazard wrote:If two sides of a triangle have lengths 2 and 5, which of the following could be the perimeter?
I. 9
II. 15
III. 19
A) None
B) I only
C) II only
D) II and III only
E) I, II, and III
OA: A
Please explain...
The third side of a triangle must be less than the sum of the other 2 sides and bigger than the difference of the other 2 sides.
Thus, given a side of 2, a side of 5, and a third side s:
5-2 < s < 5+2
3 < s < 7.
Let p = perimeter.
If s=3, p = 3+2+5 = 10.
If s=7, p = 7+2+5 = 14.
The values above give the range of the perimeter. Since 3 < s < 7, we know that 10 < p < 14.
Since none of the given perimeters are between 10 and 14, the correct answer is A.
is it greater than or equal to or simply greater than ?
Please confirm so that i can get my basic strong .
