Last visit was: 24 Apr 2026, 07:15 It is currently 24 Apr 2026, 07:15
Home
Messages
Tests
Schools
Events
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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel
Back to Forum
Create Topic
User avatar
Maria240895chile
User avatar
Joined: 23 Apr 2021
Last visit: 07 Jun 2023
Posts: 115
Own Kudos:
59
 [2]
Given Kudos: 115
Posts: 115
Kudos: 59
 [2]
A car was initially traveling at an average speed of 48 miles per hour Updated on: 31 Jan 2023, 14:24
Originally posted by Maria240895chile on 31 Jan 2023, 14:16.
Last edited by Bunuel on 31 Jan 2023, 14:24, edited 1 time in total.
Renamed the topic and edited the question.
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
C
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

35% (medium)

Question Stats:

72% (02:15) correct 28% (02:21) wrong based on 229 sessions

History

Date
Time
Result
Not Attempted Yet
A car was initially traveling at an average speed of 48 miles per hour. During each of ten successive 10-minute intervals, the car decreased its average speed by 4 miles per hour. How many miles did the car travel in the seventh 10-minute interval?

(A) 2
(B) 3
(C) 4
(D) 5
(E) 6
ShowHide Answer
Official Answer
C
User avatar
stne
User avatar
Joined: 27 May 2012
Last visit: 23 Apr 2026
Posts: 1,809
Own Kudos:
2,090
 [2]
Given Kudos: 679
Posts: 1,809
Kudos: 2,090
 [2]
A car was initially traveling at an average speed of 48 miles per hour 05 Feb 2023, 01:39
1
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
Maria240895chile
A car was initially traveling at an average speed of 48 miles per hour. During each of ten successive 10-minute intervals, the car decreased its average speed by 4 miles per hour. How many miles did the car travel in the seventh 10-minute interval?

(A) 2
(B) 3
(C) 4
(D) 5
(E) 6
Show more

During the 7th, \(10 \)min interval its speed was \(24\) miles per hour.

Travelling at \(24\) miles per hour the car would go \(4\) miles in \(10\) minutes.

Ans C

Hope it's clear.
User avatar
SaquibHGMATWhiz
User avatar
GMATWhiz Representative
Joined: 23 May 2022
Last visit: 12 Jun 2024
Posts: 623
Own Kudos:
777
Given Kudos: 6
Location: India
GMAT 1: 760 Q51 V40
Expert
Expert reply
GMAT 1: 760 Q51 V40
Posts: 623
Kudos: 777
A car was initially traveling at an average speed of 48 miles per hour 05 Feb 2023, 04:39
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Maria240895chile
A car was initially traveling at an average speed of 48 miles per hour. During each of ten successive 10-minute intervals, the car decreased its average speed by 4 miles per hour. How many miles did the car travel in the seventh 10-minute interval?

(A) 2
(B) 3
(C) 4
(D) 5
(E) 6
Show more

Solution:

  • Speed in the first 10 mins \(=48\) mph
  • Speed in the second 10 mins \(=44\) mph
  • Speed in the third 10 mins \(=40\) mph
    • Is there a pattern? Yes
    • The magnitude of speed is in AP with first term \(a=48\) and common difference \(d=-4\)
  • Speed in the seventh 10 mins \(=a+(n-1)d=48+(7-1)(-4)=48-24=24\) mph
  • So, distance traveled in the seventh 10 mins \(=speed\times time=24\times \frac{10}{60}=4\) miles

Hence the right answer is Option C
User avatar
Kjamiru
User avatar
Joined: 24 Mar 2023
Last visit: 08 Oct 2023
Posts: 2
Posts: 2
Kudos: 0
A car was initially traveling at an average speed of 48 miles per hour 27 Mar 2023, 20:10
Kudos
Add Kudos
Bookmarks
Bookmark this Post
long time reader first time commenter here. I understand how to answer the question. But my question here is why would the first interval be 48 instead of 44 MPH. is there technical wording from the question that I am missing?
User avatar
KarishmaB
User avatar
Joined: 16 Oct 2010
Last visit: 23 Apr 2026
Posts: 16,442
Own Kudos:
79,401
Given Kudos: 485
Location: Pune, India
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 16,442
Kudos: 79,401
A car was initially traveling at an average speed of 48 miles per hour 28 Mar 2023, 00:20
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Kjamiru
long time reader first time commenter here. I understand how to answer the question. But my question here is why would the first interval be 48 instead of 44 MPH. is there technical wording from the question that I am missing?
Show more

The wording of the question is a bit suspect.

The car starts out at 48 mph. During each of ten successive 10-minute intervals, the car decreased its average speed by 4 miles per hour. So the average speed starts going down and by the end of the first 10 min interval, it would be 44 mph. I would think that the decrease may be uniform over the interval such that the average speed during the interval is say 46 mph. But we are not given what the average speed during the interval is. The decrease needn't be uniform.

The speed at the start of the 7th interval will be 24 mph and will go down to 20 mph by the end of the 7th interval. The question implies that the speed reduces by 4 mph at the end of the interval.
Moderators:
Bunuel
Math Expert
109814 posts
Krunaal
Tuck School Moderator
853 posts