It is currently 22 Oct 2017, 23:55

Close

GMAT 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 GMAT 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

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

The figure above shows a row of triangular tiles each with two sides

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 41908

Kudos [?]: 129394 [0], given: 12197

The figure above shows a row of triangular tiles each with two sides [#permalink]

Show Tags

New post 09 Aug 2017, 02:13
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

100% (00:40) correct 0% (00:00) wrong based on 31 sessions

HideShow timer Statistics

Image
The figure above shows a row of triangular tiles each with two sides 15 centimeters long and one side 18 centimeters long. What is w, the width of the row, in centimeters?

(A) 10
(B) 12
(C) 15
(D) 9√2
(E) 9√3


[Reveal] Spoiler:
Attachment:
2017-08-09_1258.png
2017-08-09_1258.png [ 11.61 KiB | Viewed 328 times ]
[Reveal] Spoiler: OA

_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Kudos [?]: 129394 [0], given: 12197

Director
Director
User avatar
G
Joined: 18 Aug 2016
Posts: 512

Kudos [?]: 140 [0], given: 123

GMAT 1: 630 Q47 V29
GMAT ToolKit User Premium Member Reviews Badge
Re: The figure above shows a row of triangular tiles each with two sides [#permalink]

Show Tags

New post 09 Aug 2017, 02:18
Bunuel wrote:
Image
The figure above shows a row of triangular tiles each with two sides 15 centimeters long and one side 18 centimeters long. What is w, the width of the row, in centimeters?

(A) 10
(B) 12
(C) 15
(D) 9√2
(E) 9√3


[Reveal] Spoiler:
Attachment:
2017-08-09_1258.png


\(w = \sqrt{(15^2) - (18/2)^2} = \sqrt{225-81} = \sqrt{144} = 12\)
B
_________________

We must try to achieve the best within us

Thanks
Luckisnoexcuse

Kudos [?]: 140 [0], given: 123

BSchool Forum Moderator
User avatar
P
Joined: 26 Feb 2016
Posts: 1471

Kudos [?]: 599 [0], given: 16

Location: India
Concentration: General Management, Leadership
WE: Sales (Retail)
Premium Member CAT Tests
Re: The figure above shows a row of triangular tiles each with two sides [#permalink]

Show Tags

New post 09 Aug 2017, 03:06
Image

Formula used :
Area = 1/2 * Base * Height
Area = \(\sqrt{s(s-a)(s-b)(s-c)}\) where s is the semiperimeter(\(\frac{a+b+c}{2}\)) and a,b, and c are the three sides of the triangle

Given data : a=b=15, c=18
We can compute the semiperimeter s = \(\frac{a+b+c}{2} = \frac{48}{2} = 24\)
Therefore, the area of the triangle = \(\sqrt{24(24-15)(24-15)(24-18)}\) = \(\sqrt{24*(9)(9)(6)}\) = \(\sqrt{2^3*3*(3^2)(3^2)(2*3)}\) = \(\sqrt{2^4*3^6} = 2^2 * 3^3\)

The area of the triangle is also equal to \(\frac{1}{2} * 18 * w = 9w\)

We can equate the area of the triangle : \(3^2(w) = 2^2 * 3^3 => w = 2^2 * 3 = 12\)(Option B)
_________________

Stay hungry, Stay foolish

2017-2018 MBA Deadlines

Class of 2020: Rotman Thread | Schulich Thread
Class of 2019: Sauder Thread

Kudos [?]: 599 [0], given: 16

Manager
Manager
avatar
S
Joined: 23 Jul 2015
Posts: 147

Kudos [?]: 38 [0], given: 29

GMAT 1: 730 Q50 V40
GMAT ToolKit User CAT Tests
Re: The figure above shows a row of triangular tiles each with two sides [#permalink]

Show Tags

New post 09 Aug 2017, 03:43
In an isosceles triangle, altitude is a perpendicular bisector of the base.
Thus, \(w^2 + 9^2 = 15^2\)
\(w^2 = 225 - 81\)
\(w = \sqrt{144} = 12\) (Choice B)

Kudos [?]: 38 [0], given: 29

Director
Director
avatar
P
Joined: 22 May 2016
Posts: 833

Kudos [?]: 268 [0], given: 556

The figure above shows a row of triangular tiles each with two sides [#permalink]

Show Tags

New post 09 Aug 2017, 09:34
Bunuel wrote:
Image
The figure above shows a row of triangular tiles each with two sides 15 centimeters long and one side 18 centimeters long. What is w, the width of the row, in centimeters?

(A) 10
(B) 12
(C) 15
(D) 9√2
(E) 9√3


[Reveal] Spoiler:
Attachment:
2017-08-09_1258.png

Each triangle contains a 3-4-5 right triangle.

Width of row = altitude of one triangle.

Altitude of the isosceles triangle is a perpendicular bisector of the base; intercept point creates two right angles and divides base in half.

Base = 9. Hypotenuse = 15. Multiple of 3, and . . . Multiple of 5 . . .

If 3-4-5 right triangle is familiar, no need to calculate; 9-12-15 is common.

Answer B

Kudos [?]: 268 [0], given: 556

The figure above shows a row of triangular tiles each with two sides   [#permalink] 09 Aug 2017, 09:34
Display posts from previous: Sort by

The figure above shows a row of triangular tiles each with two sides

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


cron

GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

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

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.