Last visit was: 24 Apr 2024, 21:08 It is currently 24 Apr 2024, 21:08

Close

GRE Prep Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GRE score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel
Retired Moderator
Joined: 10 Apr 2015
Posts: 6218
Own Kudos [?]: 11681 [7]
Given Kudos: 136
Send PM
Retired Moderator
Joined: 16 Apr 2020
Status:Founder & Quant Trainer
Affiliations: Prepster Education
Posts: 1546
Own Kudos [?]: 2942 [1]
Given Kudos: 172
Location: India
WE:Education (Education)
Send PM
Intern
Intern
Joined: 11 Dec 2020
Posts: 13
Own Kudos [?]: 16 [2]
Given Kudos: 41
Send PM
Retired Moderator
Joined: 10 Apr 2015
Posts: 6218
Own Kudos [?]: 11681 [0]
Given Kudos: 136
Send PM
The lengths of two sides of isosceles triangle XYZ are 8 and 18. [#permalink]
GreenlightTestPrep wrote:
The lengths of two sides of isosceles triangle XYZ are 8 and 18.


Quantity A
Quantity B
The perimeter of triangle XYZ
36



Key property : If two sides of a triangle have lengths A and B, then . . .
the DIFFERENCE between A and B < length of third side < the SUM of A and B

Since an isosceles triangle has two the sides of equal length, there are two possible cases to consider:
case i: The three sides have lengths 8, 18 and 18
case ii: The three sides have lengths 8, 8 and 18

Important: case ii breaks the above property.
If we let the side with length 18 be the third side, we get: 8 - 8 < 18 < 8 + 8
Simplify to get: 0 < 18 < 16, which is not true.
So, case ii is impossible

Case i meets the above property, so the sides must have lengths 8, 18 and 18, which means the perimeter = 8 + 18 + 18 = 44

Answer: A
avatar
Intern
Intern
Joined: 11 Feb 2021
Posts: 1
Own Kudos [?]: 0 [0]
Given Kudos: 0
Send PM
Re: The lengths of two sides of isosceles triangle XYZ are 8 and 18. [#permalink]
D
Retired Moderator
Joined: 10 Apr 2015
Posts: 6218
Own Kudos [?]: 11681 [0]
Given Kudos: 136
Send PM
Re: The lengths of two sides of isosceles triangle XYZ are 8 and 18. [#permalink]
Mishra04 wrote:
D

The correct answer is A. See the explanations above.
Senior Manager
Senior Manager
Joined: 23 Jan 2021
Posts: 294
Own Kudos [?]: 151 [1]
Given Kudos: 81
Concentration: , International Business
Send PM
Re: The lengths of two sides of isosceles triangle XYZ are 8 and 18. [#permalink]
1
We need to be very careful. In every Question, Test maker try to fool test taker. Here is the same case. Most of test taker in rush forget to check whether their is possibility of having third side 8 or not, eventually, tend to make mistake. Likewise, in another scenario, they started to stating QUESTION like figure are not drawn to scale just to make us tempting :lol
User avatar
GRE Prep Club Legend
GRE Prep Club Legend
Joined: 07 Jan 2021
Posts: 4414
Own Kudos [?]: 68 [0]
Given Kudos: 0
Send PM
Re: The lengths of two sides of isosceles triangle XYZ are 8 and 18. [#permalink]
Hello from the GRE Prep Club BumpBot!

Thanks to another GRE Prep Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
Prep Club for GRE Bot
[#permalink]
Moderators:
Moderator
1085 posts
GRE Instructor
218 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne