Last visit was: 26 Apr 2026, 07:22 It is currently 26 Apr 2026, 07:22
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
avatar
fozzzy
Joined: 29 Nov 2012
Last visit: 17 May 2015
Posts: 573
Own Kudos:
7,007
 [9]
Given Kudos: 543
Posts: 573
Kudos: 7,007
 [9]
2
Kudos
Add Kudos
7
Bookmarks
Bookmark this Post
Most Helpful Reply
User avatar
TGC
Joined: 03 Aug 2012
Last visit: 19 Jul 2017
Posts: 572
Own Kudos:
3,621
 [8]
Given Kudos: 322
Concentration: General Management, General Management
GMAT 1: 630 Q47 V29
GMAT 2: 680 Q50 V32
GPA: 3.7
WE:Information Technology (Finance: Investment Banking)
GMAT 2: 680 Q50 V32
Posts: 572
Kudos: 3,621
 [8]
4
Kudos
Add Kudos
4
Bookmarks
Bookmark this Post
General Discussion
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 26 Apr 2026
Posts: 109,837
Own Kudos:
811,375
 [3]
Given Kudos: 105,895
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 109,837
Kudos: 811,375
 [3]
1
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
avatar
crackjack
Joined: 24 Mar 2011
Last visit: 01 Jul 2014
Posts: 38
Own Kudos:
19
 [1]
Given Kudos: 21
Location: India
Concentration: Marketing, Operations
GMAT 1: 690 Q48 V36
WE:Operations (Telecommunications)
GMAT 1: 690 Q48 V36
Posts: 38
Kudos: 19
 [1]
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
fozzzy
Mr Ben leaves his house for work at exactly 8:00 AM every morning. When he averages 40 miles per hour, he arrives at his workplace three minutes late. When he averages 60 miles per hour, he arrives three minutes early. At what average speed, in miles per hour, should Mr. Ben drive to arrive at his workplace precisely on time?

A) 45
B) 48
C) 50
D) 55
E) 58

Here is what I did

\(\frac{D}{40} - \frac{3}{60} = \frac{D}{60} + \frac{3}{60}\)

Solve this equation to get

\(D = 12\)

\(\frac{D}{40} - \frac{3}{60}\) ( will this equation give me the time?)

we get \(\frac{1}{4}\)

R * T = D

\(\frac{1}{4} * X = 12\)

X = 48

Is this correct?

I too followed the same approach. Here 8AM is an extra information.

Let the distance from house to work be x
& the right time required to reach office on time be t.

At 40 miles/hr, he is 3 minutes late from time
therefore,\(\frac{x}{40}\) = t + \(\frac{3}{60}\)

At 60 miles/hr, he is 3 minutes early
i.e. \(\frac{x}{60}\) = t - \(\frac{3}{60}\)

Now, either you equate t or subtract one equation from another,
you will get x=12

Now find t, putting x in any equation
\(\frac{12}{60}\)=t - \(\frac{3}{60}\)

t will come out to be, t = \(\frac{1}{4}\)

So Average speed to reach office precisely on time = \(\frac{x}{t}\) =\(\frac{12}{(1/4)}\) = 12*4 = 48

Ans B
avatar
crackjack
Joined: 24 Mar 2011
Last visit: 01 Jul 2014
Posts: 38
Own Kudos:
Given Kudos: 21
Location: India
Concentration: Marketing, Operations
GMAT 1: 690 Q48 V36
WE:Operations (Telecommunications)
GMAT 1: 690 Q48 V36
Posts: 38
Kudos: 19
Kudos
Add Kudos
Bookmarks
Bookmark this Post
A good thing about this question is that even if you miss the 3 minutes late/early part i.e. if by mistake solve for 3 hours late/early, you will get the same Answer, I suppose.
User avatar
iaratul
Joined: 15 May 2014
Last visit: 02 Dec 2016
Posts: 22
Own Kudos:
163
 [3]
Given Kudos: 22
Posts: 22
Kudos: 163
 [3]
Kudos
Add Kudos
3
Bookmarks
Bookmark this Post
fozzzy
Mr Ben leaves his house for work at exactly 8:00 AM every morning. When he averages 40 miles per hour, he arrives at his workplace three minutes late. When he averages 60 miles per hour, he arrives three minutes early. At what average speed, in miles per hour, should Mr. Ben drive to arrive at his workplace precisely on time?

A) 45
B) 48
C) 50
D) 55
E) 58

Here is what I did

\(\frac{D}{40} - \frac{3}{60} = \frac{D}{60} + \frac{3}{60}\)

Solve this equation to get

\(D = 12\)

\(\frac{D}{40} - \frac{3}{60}\) ( will this equation give me the time?)

we get \(\frac{1}{4}\)

R * T = D

\(\frac{1}{4} * X = 12\)

X = 48

Is this correct?

Can someone tell me is there is any problem if I try and solve it like this:

Let usual time taken = t
Distance = d

Time taken if he's 3 minutes late = t + 3
Time taken if he's 3 minutes early = t - 3

Distance, d = 40 x (t + 3) [when he's late]
Distance, d = 60 x (t - 3) [when he's early]

Hence, 40 x (t + 3) = 60 x (t - 3)
t = 15

if we plug the value of t in any of the equations:
d = 40 x (15 + 3) = 40 x 18 = 720

Average speed = Distance / Time = 720 / 15 = 48
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 26 Apr 2026
Posts: 109,837
Own Kudos:
Given Kudos: 105,895
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 109,837
Kudos: 811,375
Kudos
Add Kudos
Bookmarks
Bookmark this Post
iaratul
fozzzy
Mr Ben leaves his house for work at exactly 8:00 AM every morning. When he averages 40 miles per hour, he arrives at his workplace three minutes late. When he averages 60 miles per hour, he arrives three minutes early. At what average speed, in miles per hour, should Mr. Ben drive to arrive at his workplace precisely on time?

A) 45
B) 48
C) 50
D) 55
E) 58

Here is what I did

\(\frac{D}{40} - \frac{3}{60} = \frac{D}{60} + \frac{3}{60}\)

Solve this equation to get

\(D = 12\)

\(\frac{D}{40} - \frac{3}{60}\) ( will this equation give me the time?)

we get \(\frac{1}{4}\)

R * T = D

\(\frac{1}{4} * X = 12\)

X = 48

Is this correct?

Can someone tell me is there is any problem if I try and solve it like this:

Let usual time taken = t
Distance = d

Time taken if he's 3 minutes late = t + 3
Time taken if he's 3 minutes early = t - 3

Distance, d = 40 x (t + 3) [when he's late]
Distance, d = 60 x (t - 3) [when he's early]

Hence, 40 x (t + 3) = 60 x (t - 3)
t = 15

if we plug the value of t in any of the equations:
d = 40 x (15 + 3) = 40 x 18 = 720

Average speed = Distance / Time = 720 / 15 = 48

Yes, your approach is correct.
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 38,988
Own Kudos:
Posts: 38,988
Kudos: 1,118
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Automated notice from GMAT Club BumpBot:

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

This post was generated automatically.
Moderators:
Math Expert
109837 posts
Tuck School Moderator
852 posts