Author 
Message 
TAGS:

Hide Tags

Intern
Joined: 23 Nov 2014
Posts: 32

Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
Updated on: 03 May 2015, 13:54
Question Stats:
59% (02:45) correct 41% (02:14) wrong based on 265 sessions
HideShow timer Statistics
Annika hikes at a constant rate of 12 minutes per kilometer. She has hiked 2.75 kilometers east from the start of a hiking trail when she realizes that she has to be back at the start of the trail in 45 minutes. If Annika continues east, then turns around and retraces her path to reach the start of the trail in exactly 45 minutes, for how many kilometers total did she hike east? A) 2.25 B) 2.75 C) 3.25 D) 3.75 E) 4.25
Official Answer and Stats are available only to registered users. Register/ Login.
Originally posted by Gmatdecoder on 03 May 2015, 05:06.
Last edited by Harley1980 on 03 May 2015, 13:54, edited 1 time in total.
Changed OA



Current Student
Joined: 03 Dec 2013
Posts: 6
Concentration: Marketing, Technology

Re: Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
03 May 2015, 10:14
Sorry, I don't understand how you get 3.75. Annika has hiked 2.75 km during 33 minutes (if her constant speed is 1km every 12 min). So when she realizes she has to go back, she has 4533= 12 minutes left. It leaves her the time to advance for another 6 minutes (0,5 km). The time to go back would be 39 minutes for all the distance (2.75+0,5 = 3.25 km). My answer was C (but apparently wrong). Could you please explain what I am doing wrong? thanks



Intern
Joined: 17 Apr 2015
Posts: 5

Re: Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
03 May 2015, 10:52
I'm with you YulSob on this one, I've tried various approaches and continue to come up with C as the answer...where's Bunuel when we need him?



Intern
Joined: 23 Nov 2014
Posts: 32

Re: Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
03 May 2015, 11:43
Actually the correct answer is C) 3.25 km. This problem is from the manhattan word strategy guides and apparently there is a type that i wanted to confirm. Sorry for the trouble caused. My solution is as under; Set up two R x T =D cases. 1. 1/12 km/ min x T = 2.75
from which T= 33 mins.
We know total journey time now is 45 +33 =78. The rate is the same ie 1/12km/min.
set up second R x T =D case.
1/12 km/min x 78 = 6.5 km Now the total journey would be halved as distance would be same in each direction. 6.5/2 =3.25. C.



Manager
Joined: 09 Jan 2013
Posts: 76
Concentration: Entrepreneurship, Sustainability
GMAT 1: 650 Q45 V34 GMAT 2: 740 Q51 V39
GPA: 3.76
WE: Other (Pharmaceuticals and Biotech)

Re: Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
05 May 2015, 19:13
A slightly different way of solving with just one equation. Assume the distance to be travelled further east =x
Now in another 45 min, Annika would travel 2x + 2.75 km at a speed of 1/12 km/min.
Putting in a RTD equation 2x+2.75=45/12 x=0.5 x+2.75=3.25
Answer C



Current Student
Joined: 24 Feb 2016
Posts: 9
Location: France
Concentration: Entrepreneurship, Finance
GPA: 3

Re: Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
19 Oct 2016, 11:43
Hello Everyone,
You do not need to know that she already hiked during 33 minutes to find out the solution.
We know that she already hiked 2.75km.
She hikes one kilometer in 12 minutes, so she hikes at 5 km/h. She has 45 minutes left. So she can walk 5*(45/60) = 3.75 more kilometers.
She would have walked 2.75 + 3.75 = 6.50 km. Since the way up is as long as the way down, she hiked 6.5/2 = 3.25km
Answer C.



VP
Joined: 07 Dec 2014
Posts: 1087

Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
19 Oct 2016, 14:23
Gmatdecoder wrote: Annika hikes at a constant rate of 12 minutes per kilometer. She has hiked 2.75 kilometers east from the start of a hiking trail when she realizes that she has to be back at the start of the trail in 45 minutes. If Annika continues east, then turns around and retraces her path to reach the start of the trail in exactly 45 minutes, for how many kilometers total did she hike east?
A) 2.25 B) 2.75 C) 3.25 D) 3.75 E) 4.25 A's rate is 5kph in 3/4 hour she hikes 3.75k let d=distance from 2.75 miles east of start to turnaround point 2d+2.75=3.75k d=.5k .5k+2.75k=3.25k total distance hiking east C.



Manager
Joined: 22 Feb 2016
Posts: 96
Location: India
Concentration: Economics, Healthcare
GMAT 1: 690 Q42 V47 GMAT 2: 710 Q47 V39
GPA: 3.57

Re: Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
26 Oct 2016, 08:58
can Experts please share a event detailed solution I am so lost here.



Current Student
Joined: 26 Jan 2016
Posts: 109
Location: United States
GPA: 3.37

Re: Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
26 Oct 2016, 10:15
Since Annika has already hiked 2.75 km if she were to turn around at that moment it would take her 33 minutes to return home. She has 45 minutes to return home. 4533=12. She needs half of that time to return. So if you split the remaining 12 minutes in half (one half travel east, one half return home) she has 6 additional minutes to walk east which is .5 km. So 2.75+.5=3.25 km.



Current Student
Joined: 18 Oct 2014
Posts: 874
Location: United States
GPA: 3.98

Re: Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
26 Oct 2016, 10:48
Gmatdecoder wrote: Annika hikes at a constant rate of 12 minutes per kilometer. She has hiked 2.75 kilometers east from the start of a hiking trail when she realizes that she has to be back at the start of the trail in 45 minutes. If Annika continues east, then turns around and retraces her path to reach the start of the trail in exactly 45 minutes, for how many kilometers total did she hike east?
A) 2.25 B) 2.75 C) 3.25 D) 3.75 E) 4.25 Lemme try explaining how I solved the question. A can hike 1 kms in 12 minutes. So in 45 minutes she can hike 3.75 kms. No she has hiked 2.75 kms when she realized that she has to return to the starting point. Basically, she has to cover 3.75 kms in 45 mins. Since she has already hiked 2.75 Kms and this distance has to be covered on her way back in those 45 minutes, she is left with only 3.752.75= 1 km. And in this 1 km, she has to travel towards east and then return i.e. she will cover .5 kms to the east and .5kms return distance. So she traveled total of 2.75+.5= 3.25 kms towards east C is the answer
_________________
I welcome critical analysis of my post!! That will help me reach 700+



Intern
Joined: 17 Oct 2014
Posts: 1

Re: Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
02 Oct 2017, 11:15
Here's my explaination
Annika covered
1km in 12 mins 2km in 24 mins 3km in 36 mins 4km in 48 mins
She travelled 83.3mts/min (1000mts/12mins)
83.3*3 = 249.9mts
In 45 mins she travelled 4  2.49 = 3.75.
Answer D
Posted from my mobile device



VP
Status: Learning
Joined: 20 Dec 2015
Posts: 1190
Location: India
Concentration: Operations, Marketing
GPA: 3.4
WE: Engineering (Manufacturing)

Re: Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
02 Oct 2017, 19:51
Gmatdecoder wrote: Annika hikes at a constant rate of 12 minutes per kilometer. She has hiked 2.75 kilometers east from the start of a hiking trail when she realizes that she has to be back at the start of the trail in 45 minutes. If Annika continues east, then turns around and retraces her path to reach the start of the trail in exactly 45 minutes, for how many kilometers total did she hike east?
A) 2.25 B) 2.75 C) 3.25 D) 3.75 E) 4.25 The answer is C Total distance traveled in 45 min = 45*1/12=15/4=3.75 Now this 3.75 contains 2.75 and the distance x that she traveled when she realized that she had to go back in 45 min. Now this x distance is covered twice in 45 min minutes once due east and once while returning . So 2x+2.75=3.75 2x=1 therefore x=0.5 Now total distance hiked due east =2.75+0.5=3.25
_________________
Please give kudos if you found my answers useful



CEO
Joined: 12 Sep 2015
Posts: 2848
Location: Canada

Re: Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
03 Apr 2018, 10:06
Gmatdecoder wrote: Annika hikes at a constant rate of 12 minutes per kilometer. She has hiked 2.75 kilometers east from the start of a hiking trail when she realizes that she has to be back at the start of the trail in 45 minutes. If Annika continues east, then turns around and retraces her path to reach the start of the trail in exactly 45 minutes, for how many kilometers total did she hike east?
A) 2.25 B) 2.75 C) 3.25 D) 3.75 E) 4.25 Annika's speed 12 minutes per kilometer In other words, she walks at a speed of 1/12 kilometer per minute. She has already waked 2.75 km Let x = the additional # number of km she walks EAST before turning around. This means the number of kilometers she will hike from this point = x + x + 2.75 kilometers She must walk this distance in 45 minutes at a rate of 1/12 kilometer per minuteDistance = (rate)(time) So, x + x + 2.75 = (1/12)(45) 2.75 + 2x = 3.75 2x = 1 x = 0.5So, the TOTAL distance Annika walks EAST = 2.75 + 0.5 = 3.25 Answer: C Cheers, Brent
_________________
Brent Hanneson – GMATPrepNow.com
Sign up for our free Question of the Day emails



Manager
Joined: 08 Sep 2016
Posts: 117

Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
03 Apr 2018, 13:10
The way I approached this problem was by finding the total time that Annika hiked first. Rate given = 12km/min
The question says that she had already traveled 2.75 km east. In this time, she traveled 2.75 km * (12min/1km)= 33 minutes.
Next, we are told that she has 45 minutes to return back to the start of the trail. So we should add the 33 minutes that she had already hiked to the 45 minutes she has to make it back to the start of the trail. 33+ 45 = 78.
In total, she will be moving for 78 minutes.
Take the total time and multiply it by her rate. (Careful here because the rate was provided in minutes/km. You have to either invert the given rate or calculated total time).
78 min *( 1km/12min) = 13/2 miles = 6.5 miles.
Total travel distance 6.5 miles. We are told she traveled 2.75 miles and then continued east before turning around. If you divide 6.5 km in half, you will get 3.25. this is the halfway mark for the total trip.



Target Test Prep Representative
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2835

Re: Annika hikes at a constant rate of 12 minutes per kilometer. She.....
[#permalink]
Show Tags
05 Apr 2018, 17:02
Gmatdecoder wrote: Annika hikes at a constant rate of 12 minutes per kilometer. She has hiked 2.75 kilometers east from the start of a hiking trail when she realizes that she has to be back at the start of the trail in 45 minutes. If Annika continues east, then turns around and retraces her path to reach the start of the trail in exactly 45 minutes, for how many kilometers total did she hike east?
A) 2.25 B) 2.75 C) 3.25 D) 3.75 E) 4.25 If her rate is 12 minutes per kilometer, then in 60 minutes, or in 1 hour, she walks 5 kilometers, and thus her rate is 5 km/hr. Since 45 minutes = 3/4 hour, in 45 minutes Anika travels 5 x 3/4 = 15/4 = 3.75 km. She has already walked 2.75 km, and she will walk an additional 3.75 km in the next 45 minutes. So, in total, she will have traveled 2.75 + 3.75 = 6.5 km for her entire hike. Thus, she has to turn around when she is at the halfway point, when she has traveled 6.5/2 = 3.25 km east. Answer: C
_________________
Jeffery Miller
Head of GMAT Instruction
GMAT Quant SelfStudy Course
500+ lessons 3000+ practice problems 800+ HD solutions




Re: Annika hikes at a constant rate of 12 minutes per kilometer. She..... &nbs
[#permalink]
05 Apr 2018, 17:02






