GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 19 Feb 2019, 07:46

### 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

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

## Events & Promotions

###### Events & Promotions in February
PrevNext
SuMoTuWeThFrSa
272829303112
3456789
10111213141516
17181920212223
242526272812
Open Detailed Calendar
• ### Free GMAT Prep Hour

February 20, 2019

February 20, 2019

08:00 PM EST

09:00 PM EST

Strategies and techniques for approaching featured GMAT topics. Wednesday, February 20th at 8 PM EST

February 21, 2019

February 21, 2019

10:00 PM PST

11:00 PM PST

Kick off your 2019 GMAT prep with a free 7-day boot camp that includes free online lessons, webinars, and a full GMAT course access. Limited for the first 99 registrants! Feb. 21st until the 27th.

# If the perimeter of semicircle C is 4+4π, what is the radius of C?

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 52971
If the perimeter of semicircle C is 4+4π, what is the radius of C?  [#permalink]

### Show Tags

15 Sep 2016, 03:10
00:00

Difficulty:

65% (hard)

Question Stats:

52% (01:24) correct 48% (01:10) wrong based on 124 sessions

### HideShow timer Statistics

If the perimeter of semicircle C is 4+4π, what is the radius of C?

A. 4+4/π
B. 4
C. (4+4π)/(2+π)
D. 2+2/(√π)
E. 2

Attachment:

T6429.png [ 4.47 KiB | Viewed 2277 times ]

_________________
Director
Joined: 04 Jun 2016
Posts: 568
GMAT 1: 750 Q49 V43
If the perimeter of semicircle C is 4+4π, what is the radius of C?  [#permalink]

### Show Tags

Updated on: 19 Sep 2016, 08:34
Bunuel wrote:

If the perimeter of semicircle C is 4+4π, what is the radius of C?

A. 4+4/π
B. 4
C. (4+4π)/(2+π)
D. 2+2/(√π)
E. 2

Attachment:
T6429.png

Perimeter of a circle is $$2πr$$

Therefore perimeter of a semi-circle will be = half of perimeter of the circle, but notice that now the perimeter contains a straight line also (the diameter) which is 2r in length. This should also be added to calculate the perimeter of the semi-circle

$$\frac{1}{2} * 2πr + (2r)$$ =$$πr+2r$$

It is given that perimeter of semi-circle is $$4+4π$$

$$πr+2r= 4+4π$$

$$r(2+π)= 4+4π$$

$$r= \frac{4+4π}{2+π}$$

_________________

Posting an answer without an explanation is "GOD COMPLEX". The world doesn't need any more gods. Please explain you answers properly.
FINAL GOODBYE :- 17th SEPTEMBER 2016. .. 16 March 2017 - I am back but for all purposes please consider me semi-retired.

Originally posted by LogicGuru1 on 15 Sep 2016, 03:38.
Last edited by LogicGuru1 on 19 Sep 2016, 08:34, edited 5 times in total.
Retired Moderator
Joined: 26 Nov 2012
Posts: 592
Re: If the perimeter of semicircle C is 4+4π, what is the radius of C?  [#permalink]

### Show Tags

15 Sep 2016, 04:08
Bunuel wrote:

If the perimeter of semicircle C is 4+4π, what is the radius of C?

A. 4+4/π
B. 4
C. (4+4π)/(2+π)
D. 2+2/(√π)
E. 2

Attachment:
T6429.png

Perimeter of semi-circle = r(π+2)

r(π+2) = 4+4π = > r = 4+4π/(π+2).

IMO option C.
Senior Manager
Joined: 11 Nov 2014
Posts: 331
Location: India
WE: Project Management (Telecommunications)
Re: If the perimeter of semicircle C is 4+4π, what is the radius of C?  [#permalink]

### Show Tags

15 Sep 2016, 04:31
4+4π = semi
r = 8+8π/2π
r=4+4π/π

A
Intern
Joined: 03 Sep 2016
Posts: 1
Re: If the perimeter of semicircle C is 4+4π, what is the radius of C?  [#permalink]

### Show Tags

15 Sep 2016, 20:05
It will be done as
Perimeter of semicircle will be arc length + straight length.. so Pi*r+2r ..

So,r(Pi+2)=4+4Pi
r = ( 4+4Pi)/ (2+Pi)
Board of Directors
Status: Stepping into my 10 years long dream
Joined: 18 Jul 2015
Posts: 3631
Re: If the perimeter of semicircle C is 4+4π, what is the radius of C?  [#permalink]

### Show Tags

17 Sep 2016, 05:04
paidlukkha wrote:
4+4π = semi
r = 8+8π/2π
r=4+4π/π

A

You have missed something here. What is semi here?

Note : Semi Circle Perimeter = πr + 2r, 2r is the length of the diameter.
_________________

My GMAT Story: From V21 to V40
My MBA Journey: My 10 years long MBA Dream
My Secret Hacks: Best way to use GMATClub | Importance of an Error Log!
Verbal Resources: All SC Resources at one place | All CR Resources at one place

GMAT Club Inbuilt Error Log Functionality - View More.
New Visa Forum - Ask all your Visa Related Questions - here.
New! Best Reply Functionality on GMAT Club!
Find a bug in the new email templates and get rewarded with 2 weeks of GMATClub Tests for free
Check our new About Us Page here.

Intern
Joined: 27 May 2015
Posts: 2
Re: If the perimeter of semicircle C is 4+4π, what is the radius of C?  [#permalink]

### Show Tags

17 Sep 2016, 21:25

Sent from my ONE A2003 using GMAT Club Forum mobile app
Non-Human User
Joined: 09 Sep 2013
Posts: 9846
Re: If the perimeter of semicircle C is 4+4π, what is the radius of C?  [#permalink]

### Show Tags

05 Oct 2018, 15:13
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.
_________________
Re: If the perimeter of semicircle C is 4+4π, what is the radius of C?   [#permalink] 05 Oct 2018, 15:13
Display posts from previous: Sort by