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

It is currently 16 Oct 2018, 07:26

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

A circular jogging track forms the edge of a circular lake that has a

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

Hide Tags

Intern
Intern
avatar
Joined: 12 May 2013
Posts: 8
GPA: 3.7
Reviews Badge
A circular jogging track forms the edge of a circular lake that has a  [#permalink]

Show Tags

New post Updated on: 18 Oct 2015, 09:49
1
14
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

73% (01:40) correct 27% (01:47) wrong based on 569 sessions

HideShow timer Statistics

A circular jogging track forms the edge of a circular lake that has a diameter of 2 miles. Johanna walked once around the track at the average speed of 3 miles per hour. If t represents the number of hours it took Johanna to walk completely around the lake, which of the following is a correct statement?

A. 0.5< t < 0.75
B. 1.75< t < 2.0
C. 2.0 < t < 2.5
D. 2.5 < t < 3.0
E. 3 < t < 3.5

Originally posted by novice12 on 18 Oct 2015, 09:41.
Last edited by Bunuel on 18 Oct 2015, 09:49, edited 2 times in total.
Renamed the topic and edited the question.
Verbal Forum Moderator
User avatar
V
Status: Greatness begins beyond your comfort zone
Joined: 08 Dec 2013
Posts: 2085
Location: India
Concentration: General Management, Strategy
Schools: Kelley '20, ISB '19
GPA: 3.2
WE: Information Technology (Consulting)
GMAT ToolKit User Reviews Badge CAT Tests
Re: A circular jogging track forms the edge of a circular lake that has a  [#permalink]

Show Tags

New post 18 Oct 2015, 10:11
1
1
Diameter =2
Radius = 1
Circumference = 2 pi * 1 = 2 pi
Speed = 3 miles/ hour
Time , t= Distance / Speed
t = 2 pi / 3 = 2* 3.14 / 3 = 2* 1.05 = 2.10 approx
2.0< t < 2.5
Answer C
_________________

When everything seems to be going against you, remember that the airplane takes off against the wind, not with it. - Henry Ford
The Moment You Think About Giving Up, Think Of The Reason Why You Held On So Long
+1 Kudos if you find this post helpful

Board of Directors
User avatar
P
Joined: 17 Jul 2014
Posts: 2653
Location: United States (IL)
Concentration: Finance, Economics
GMAT 1: 650 Q49 V30
GPA: 3.92
WE: General Management (Transportation)
GMAT ToolKit User Premium Member Reviews Badge
Re: A circular jogging track forms the edge of a circular lake that has a  [#permalink]

Show Tags

New post 18 Oct 2015, 13:19
D=2, and R=1
circumference thus is 2pi miles
we know that she walked 3mph
knowing the formula rt=D, we can deduce that t= D/r
D is 2pi miles and r is 3mph
t = 2pi/3
pi can be rewritten as 22/7
2*22/7 = 44/7 and multiply this by 1/3 = 44/21. This is greater than 2, but less than 2.5, therefore, 2<t<2.5. Answer choice C.
Director
Director
User avatar
D
Joined: 04 Dec 2015
Posts: 701
Location: India
Concentration: Technology, Strategy
Schools: ISB '19, IIMA , IIMB, XLRI
WE: Information Technology (Consulting)
GMAT ToolKit User
A circular jogging track forms the edge of a circular lake that has a  [#permalink]

Show Tags

New post 09 Sep 2017, 07:12
1
novice12 wrote:
A circular jogging track forms the edge of a circular lake that has a diameter of 2 miles. Johanna walked once around the track at the average speed of 3 miles per hour. If t represents the number of hours it took Johanna to walk completely around the lake, which of the following is a correct statement?

A. 0.5< t < 0.75
B. 1.75< t < 2.0
C. 2.0 < t < 2.5
D. 2.5 < t < 3.0
E. 3 < t < 3.5

Diameter of circular lake \(= 2\) miles

Diameter \(= 2r\) ------- (\(r\) is the radius of circular lake)

Circumference of circular lake \(= 2\pi\)\(r\) \(= 2\pi\)

Average speed \(= 3\) miles/hour

\(Time (t)= \frac{distance}{speed} = \frac{Circumference}{speed} = \frac{2\pi}{3}\) ---------- (we can approximate value of \(\pi\) to \(3.1\))

Time \((t) = \frac{2*3.1}{3} = \frac{6.2}{3} = 2.0666\)

\(2.0666\) comes between \(2.0\) and \(2.5\). Therefore \(2.0 < t < 2.5\)

Answer (C)...

_________________
Please Press "+1 Kudos" to appreciate. :-)
Intern
Intern
avatar
B
Joined: 04 Feb 2018
Posts: 7
Re: A circular jogging track forms the edge of a circular lake that has a  [#permalink]

Show Tags

New post 04 Apr 2018, 14:15
Diameter = 2 miles
Circumference of the lake = 2.pi.r = 2r.pi = D.pi = 2.pi

t = (circumference) / avg speed = (2.pi) / 3 = (2/3).pi

Now, pi = 22/7, therefore, t = (2/3).(22/7)

To make the multiplication easy - let's change the value of 22 to 21 in one case, and 24 in the other.

* When we change it to 21, then t > (2/3).(21/7) = 2
* When we change it to 24, then t < (2/3).(24/7) = 16/7 = ~2.27

Therefore, 2.0 < t < 2.27 --- the only answer that fits this is C
Target Test Prep Representative
User avatar
G
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2830
Re: A circular jogging track forms the edge of a circular lake that has a  [#permalink]

Show Tags

New post 10 Apr 2018, 11:15
novice12 wrote:
A circular jogging track forms the edge of a circular lake that has a diameter of 2 miles. Johanna walked once around the track at the average speed of 3 miles per hour. If t represents the number of hours it took Johanna to walk completely around the lake, which of the following is a correct statement?

A. 0.5< t < 0.75
B. 1.75< t < 2.0
C. 2.0 < t < 2.5
D. 2.5 < t < 3.0
E. 3 < t < 3.5


If the lake has a diameter of 2 miles, then its circumference (which is the length of the track) is 2 x π = 2π miles long. Since Johanna’s speed is 3 miles per hour, then the time it took her to walk around the lake is 2π/3 hours. Since π ≈ 3.14, so 2π/3 ≈ 6.28/3 ≈ 6.3/3 = 2.1 hours.

Answer: C
_________________

Jeffery Miller
Head of GMAT Instruction

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

VP
VP
User avatar
V
Status: It's near - I can see.
Joined: 13 Apr 2013
Posts: 1264
Location: India
Concentration: International Business, Operations
GMAT 1: 480 Q38 V22
GPA: 3.01
WE: Engineering (Consulting)
Premium Member Reviews Badge CAT Tests
Re: A circular jogging track forms the edge of a circular lake that has a  [#permalink]

Show Tags

New post 12 Apr 2018, 06:09
novice12 wrote:
A circular jogging track forms the edge of a circular lake that has a diameter of 2 miles. Johanna walked once around the track at the average speed of 3 miles per hour. If t represents the number of hours it took Johanna to walk completely around the lake, which of the following is a correct statement?

A. 0.5< t < 0.75
B. 1.75< t < 2.0
C. 2.0 < t < 2.5
D. 2.5 < t < 3.0
E. 3 < t < 3.5


Diameter = 2 miles

Radius = 1 mile

Distance = Circumference = 2 * pi * r = 2 * 3.1 * 1

Circumference = 6.2 miles approx.

Speed = 3 miles/hr

Time = 6.2/3

Time = 2.06 approx

Hence (C)
_________________

"Do not watch clock; Do what it does. KEEP GOING."

Intern
Intern
avatar
B
Joined: 02 Apr 2018
Posts: 20
GMAT ToolKit User
Re: A circular jogging track forms the edge of a circular lake that has a  [#permalink]

Show Tags

New post 11 Jun 2018, 09:08
Diameter is 2. So radius is 1.

Time = Distance/Speed = 2*pi*1(Circumference)/3

Now pi = 3.14. So 3.14 / 3 is approximately one.

So t is greater than 2 but very near to 2
Manager
Manager
avatar
S
Joined: 14 Jul 2014
Posts: 103
Location: India
Concentration: Social Entrepreneurship, Strategy
GMAT 1: 620 Q41 V34
WE: Information Technology (Computer Software)
Re: A circular jogging track forms the edge of a circular lake that has a  [#permalink]

Show Tags

New post 29 Aug 2018, 11:47
novice12 wrote:
A circular jogging track forms the edge of a circular lake that has a diameter of 2 miles. Johanna walked once around the track at the average speed of 3 miles per hour. If t represents the number of hours it took Johanna to walk completely around the lake, which of the following is a correct statement?

A. 0.5< t < 0.75
B. 1.75< t < 2.0
C. 2.0 < t < 2.5
D. 2.5 < t < 3.0
E. 3 < t < 3.5


2 concepts majorly used here.
1. Distance = Speed * Time
2. Circumference of the circle= 2*Pie*r
GMAT Club Bot
Re: A circular jogging track forms the edge of a circular lake that has a &nbs [#permalink] 29 Aug 2018, 11:47
Display posts from previous: Sort by

A circular jogging track forms the edge of a circular lake that has a

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


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| 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®.