BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Pyramid Geometry Data Sufficiency Question

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Senior | Next Rank: 100 Posts
Posts: 37
Joined: Wed Feb 25, 2015 6:00 pm
Thanked: 1 times

Pyramid Geometry Data Sufficiency Question

by infiniti007 » Wed Jul 15, 2015 11:22 pm
Any help on how to solve the following problem would be appreciated.

A pyramid-shaped box to protect a plant is constructed with 4 lateral faces and an open bottom. What is the lateral area of the box?

1.) The base of the pyramid is a polygon with all sides of equal length and the perimeter of the base is 1 meter.

2.) The lateral faces are isosceles triangles that have the same size and shape.
Top
Source: — Data Sufficiency |
User avatar
GMAT Instructor
Posts: 15539
Joined: Tue May 25, 2010 12:04 pm
Location: New York, NY
Thanked: 13060 times
Followed by:1906 members
GMAT Score:790

by GMATGuruNY » Thu Jul 16, 2015 3:27 am
infiniti007 wrote:Any help on how to solve the following problem would be appreciated.

A pyramid-shaped box to protect a plant is constructed with 4 lateral faces and an open bottom. What is the lateral area of the box?

1.) The base of the pyramid is a polygon with all sides of equal length and the perimeter of the base is 1 meter.

2.) The lateral faces are isosceles triangles that have the same size and shape.
Even when the statements are combined, the height of each triangle serving to form the pyramid is not constrained.
Each of the triangles could have a height of 1 meter or of 100 meters.
Since different heights are possible, the lateral area of the box cannot be determined.

The correct answer is E.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
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].
Student Review #1
Student Review #2
Student Review #3
Top
User avatar
MBA Admissions Consultant
Posts: 2279
Joined: Fri Nov 11, 2011 7:51 am
Location: New York
Thanked: 660 times
Followed by:266 members
GMAT Score:770

by Jim@StratusPrep » Thu Jul 16, 2015 3:56 am
I always try to think about what can be changed about shape. In this instance the height of the triangles is movable. If it is movable, aka it can be smaller or larger, then there are multiple values.

Also, you aren't likely to see the term 'lateral area' on the GMAT, but it is referring to the surface area.
GMAT Answers provides a world class adaptive learning platform.
-- Push button course navigation to simplify planning
-- Daily assignments to fit your exam timeline
-- Organized review that is tailored based on your abiility
-- 1,000s of unique GMAT questions
-- 100s of handwritten 'digital flip books' for OG questions
-- 100% Free Trial and less than $20 per month after.
-- Free GMAT Quantitative Review

Image
Top
Legendary Member
Posts: 712
Joined: Fri Sep 25, 2015 4:39 am
Thanked: 14 times
Followed by:5 members

by Mo2men » Thu Oct 08, 2015 12:19 am
GMATGuruNY wrote:
infiniti007 wrote:Any help on how to solve the following problem would be appreciated.

A pyramid-shaped box to protect a plant is constructed with 4 lateral faces and an open bottom. What is the lateral area of the box?

1.) The base of the pyramid is a polygon with all sides of equal length and the perimeter of the base is 1 meter.

2.) The lateral faces are isosceles triangles that have the same size and shape.
Even when the statements are combined, the height of each triangle serving to form the pyramid is not constrained.
Each of the triangles could have a height of 1 meter or of 100 meters.
Since different heights are possible, the lateral area of the box cannot be determined.

The correct answer is E.
HiGMATGuruNY,
I have a question, when we say that the pyramid has 4 lateral faces, does it mean that the bottom consists of polygon of 4 sides? or is there is another possibility?

Thanks
Top
User avatar
Legendary Member
Posts: 1100
Joined: Sat May 10, 2014 11:34 pm
Location: New Delhi, India
Thanked: 205 times
Followed by:24 members

by GMATinsight » Thu Oct 08, 2015 1:01 am
infiniti007 wrote:Any help on how to solve the following problem would be appreciated.

A pyramid-shaped box to protect a plant is constructed with 4 lateral faces and an open bottom. What is the lateral area of the box?

1.) The base of the pyramid is a polygon with all sides of equal length and the perimeter of the base is 1 meter.

2.) The lateral faces are isosceles triangles that have the same size and shape.

Question : Lateral Area = ?

Statement 1: The base of the pyramid is a polygon with all sides of equal length, and the perimeter of the base is 1 meter.
Since the Number of sides in base =4
Perimeter i.e. 4*Side = 1
i.e. Side = 1/4
But the height of the pyramid is unknown rendering to different values of lateral faces for different height of Pyramid. Hence,
NOT SUFFICIENT

Statement 2: The lateral faces are isosceles triangles that have the same size and shape.
But the height of the pyramid and Side of base quadrilateral are unknown rendering to different values of lateral faces for different height of Pyramid. Hence,
NOT SUFFICIENT

Combining the two statements
Side of Base = 1/4
All faces are Isosceles but the heights can be different rendering different values of Area of Lateral Surface Area. Hence,
NOT SUFFICIENT

Answer: option E
"GMATinsight"Bhoopendra Singh & Sushma Jha
Most Comprehensive and Affordable Video Course 2000+ CONCEPT Videos and Video Solutions
Whatsapp/Mobile: +91-9999687183 l [email protected]
Contact for One-on-One FREE ONLINE DEMO Class Call/e-mail
Most Efficient and affordable One-On-One Private tutoring fee - US$40-50 per hour
Top
User avatar
Legendary Member
Posts: 1100
Joined: Sat May 10, 2014 11:34 pm
Location: New Delhi, India
Thanked: 205 times
Followed by:24 members

by GMATinsight » Thu Oct 08, 2015 1:02 am
Mo2men wrote: I have a question, when we say that the pyramid has 4 lateral faces, does it mean that the bottom consists of polygon of 4 sides? or is there is another possibility?

Thanks
Yes, 4 lateral faces mean that the base is a quadrilateral.

You are right about it.

I hope this helps!
"GMATinsight"Bhoopendra Singh & Sushma Jha
Most Comprehensive and Affordable Video Course 2000+ CONCEPT Videos and Video Solutions
Whatsapp/Mobile: +91-9999687183 l [email protected]
Contact for One-on-One FREE ONLINE DEMO Class Call/e-mail
Most Efficient and affordable One-On-One Private tutoring fee - US$40-50 per hour
Top
Post new topic Post Reply
• Page 1 of 1