It is currently 24 Feb 2018, 10:19

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

ABC is a right angled triangle with BC=6cm and AB=8 cm

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

Hide Tags

2 KUDOS received
Intern
Intern
avatar
Joined: 21 Jan 2013
Posts: 7
Location: India
WE: Engineering (Telecommunications)
ABC is a right angled triangle with BC=6cm and AB=8 cm [#permalink]

Show Tags

New post 18 Jan 2014, 06:52
2
This post received
KUDOS
5
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  55% (hard)

Question Stats:

61% (01:29) correct 39% (02:08) wrong based on 101 sessions

HideShow timer Statistics

Attachment:
1796929.png
1796929.png [ 6.54 KiB | Viewed 76512 times ]
ABC is a right angled triangle with BC = 6 cm and AB = 8 cm. AC is hypotenuse. A circle with centre O and radius x has been inscribed. What is the value of x.

A. 2.4 cm
B. 2 cm
C. 3.6 cm
D. 4 cm
E. 3 cm
[Reveal] Spoiler: OA
1 KUDOS received
Manager
Manager
User avatar
Joined: 23 Jun 2008
Posts: 85
Location: Australia
Schools: AGSM '22
GMAT Date: 04-01-2014
Re: ABC is a right angled triangle with BC=6cm and AB=8 cm [#permalink]

Show Tags

New post 19 Jan 2014, 14:28
1
This post received
KUDOS
005ashok wrote:
ABC is a right angled triangle with BC=6cm and AB=8 cm. AC is hypotenuse. A circle with centre O and radius x has been inscribed. What is the value of x.

a. 2.4 cm
b.2 cm
c.3.6 cm
d.4 cm
e.3 cm



Answer is 2.

detailed explanation is given here: http://mathforum.org/library/drmath/view/54670.html
_________________


Kudos (+1) if you find this post helpful. :)

2 KUDOS received
SVP
SVP
User avatar
S
Joined: 14 Apr 2009
Posts: 2146
Location: New York, NY
Re: ABC is a right angled triangle with BC=6cm and AB=8 cm [#permalink]

Show Tags

New post 19 Jan 2014, 17:24
2
This post received
KUDOS
3
This post was
BOOKMARKED
005ashok wrote:
ABC is a right angled triangle with BC=6cm and AB=8 cm. AC is hypotenuse. A circle with centre O and radius x has been inscribed. What is the value of x.

a. 2.4 cm
b.2 cm
c.3.6 cm
d.4 cm
e.3 cm



Once you have circle inscribed into that triangle -- you'll notice you won't have the traditional tips to solve this question. This is a 3-4-5 triangle but the angles are not the typical 30-60-90 degree triangle. Instead you have so solve for r - radius.

The way to solve this is to draw a line from radius to all 3 vertices - so you have 3 separate lines. This creates OA, OB, and OC and 3 smaller triangles within the larger 6-8-10 triangle. THe sum of the 3 smaller triangles should equal the sum of the large triangle.

The reason we care about the smaller triangles is because we know their "height" is going to be "r". So 1/2 * base * height, the height will be r.

1/2 * 6* r + 1/2 * 8 * r + 1/2 * 10 * r = 1/2 * 8 * 6
12r = 24
r = 2
Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 13764
Premium Member
Re: ABC is a right angled triangle with BC=6cm and AB=8 cm [#permalink]

Show Tags

New post 05 Jul 2015, 12:11
Hello from the GMAT Club BumpBot!

Thanks to another GMAT 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.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Manager
Manager
User avatar
Joined: 21 Jun 2014
Posts: 143
Location: United States
Concentration: General Management, Strategy
GMAT 1: 630 Q45 V31
GPA: 3.4
WE: Engineering (Computer Software)
Re: ABC is a right angled triangle with BC=6cm and AB=8 cm [#permalink]

Show Tags

New post 06 Jul 2015, 07:12
This is a right angled triangle with sides 6 and 8 .Third side will be 10(Pythagorean triplets) .
The circle is inscribed in the triangle . So all the three sides are at tangent to the circle .A line drawn from center of the circle will be perpendicular to the sides of the triangle

Area of triangle :6*8=48
The larger triangle can be broken into three smaller triangles with base =8,height=r ,base=10,height=r ,base 6 height=r .
Sum of areas of these three triangle :8r+10r+6r=24r .24r=48 ,hence r=2 .Option B

Regards,
Manish Khare
_________________

Regards,
Manish Khare
"Every thing is fine at the end. If it is not fine ,then it is not the end "

Senior Manager
Senior Manager
avatar
Joined: 27 Dec 2013
Posts: 298
Re: ABC is a right angled triangle with BC=6cm and AB=8 cm [#permalink]

Show Tags

New post 06 Jul 2015, 09:39
Hi All,

My answer is 1.92 (The closest answer is 2)

My work as follows.

The area of the right triangle should be same which ever be the base.

1/2 * 8 *6= 1/2 * 10 * h (h= the altitube drawn to the hypotenuse)

h= 4.8.


h= BO+ OP.

B0 = sqrt 2 * r (diagnoal of a square)

OP= r= Radius.

sqrt 2 * r + r= 4.8== r = 1.92


Please let me know whether I am correct.


005ashok wrote:
Attachment:
1796929.png
ABC is a right angled triangle with BC = 6 cm and AB = 8 cm. AC is hypotenuse. A circle with centre O and radius x has been inscribed. What is the value of x.

A. 2.4 cm
B. 2 cm
C. 3.6 cm
D. 4 cm
E. 3 cm

_________________

Kudos to you, for helping me with some KUDOS.

Intern
Intern
avatar
Joined: 01 Jun 2013
Posts: 9
Re: ABC is a right angled triangle with BC=6cm and AB=8 cm [#permalink]

Show Tags

New post 27 Dec 2015, 09:22
The formula for r is when circle is inscribed in right triangle is -

Perpendicular+base-hypotenuses =2 r

Let me know if someone wants to know the derivation.:)
Retired Moderator
User avatar
P
Joined: 12 Aug 2015
Posts: 2428
GRE 1: 323 Q169 V154
GMAT ToolKit User Premium Member
Re: ABC is a right angled triangle with BC=6cm and AB=8 cm [#permalink]

Show Tags

New post 03 Apr 2016, 21:06
There are two ways as far as i know
i will use the area formula as that is more likely to hit my mind first
although the rule states that for any circle to be inscribed in an 90 triangle => the radius => P+B -H/2 where P,B,H are three sides of the triangle and H being the largest
_________________


Getting into HOLLYWOOD with an MBA

Stone Cold's Mock Tests for GMAT-Quant(700+)

Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 13764
Premium Member
Re: ABC is a right angled triangle with BC=6cm and AB=8 cm [#permalink]

Show Tags

New post 19 Apr 2017, 04:28
Hello from the GMAT Club BumpBot!

Thanks to another GMAT 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.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Re: ABC is a right angled triangle with BC=6cm and AB=8 cm   [#permalink] 19 Apr 2017, 04:28
Display posts from previous: Sort by

ABC is a right angled triangle with BC=6cm and AB=8 cm

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


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®.