BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

★★★★★5.0559 reviews
GMATLiveTeach 7 seats left
Chris Peckover
NEXT LIVE COHORT

Oct 13 to Jan 7, 2027

with Chris Peckover

Schedule
Tue, Thu · 8:00 to 10:00 PM ET
Included
40 live hours + 6 months of GMAT OnDemand
  • Live instruction and real-time questions
  • Class recordings and assigned practice
View class & enroll
Limited cohort · enrollment openTarget Test Prep
EALiveTeach 5 seats left
Logan Thompson
EXECUTIVE ASSESSMENT

Sep 6 to Dec 6, 2026

with Logan Thompson

Schedule
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes plus six months of access to the complete TTP EA OnDemand course.
  • 165+ EA Score Guarantee
  • 4,100+ Quant, Verbal, and Integrated Reasoning practice questions
  • 400+ hours of in-depth video lessons
  • 3,000+ step-by-step video solutions
View EA class & enroll
Limited cohort · enrollment openTarget Test Prep
GMATOnDemand Start anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

715+ score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions
Start free 5-day trial
Read 559 reviewsTarget Test Prep

Compare the format, schedule, and included access before enrolling. Prices and seat counts shown reflect the supplied offer details.

To find the average speed

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Legendary Member
Posts: 641
Joined: Tue Feb 14, 2012 3:52 pmFollowed by: 8 members
Thanked: 11 times
by gmattesttaker2 » Mon Dec 23, 2013 11:04 pm
Hello,

Can you please assist with this:

If it took a sports car and a truck the same time to travel distances of 120 and 100
miles, respectively, what was the average speed of the truck?

(1) It took the car 30 minutes to travel half of the distance.

(2) The average speed of the truck was ten miles per hour less than the average speed of
the car.


OA: B


I am trying to solve as follows:

Since it took the sports car and the truck the same time to travel distances of 120 and 100, let the time be "t"

Rate x Time = Distance
r1 x t = 120 (For Sports car)
r2 x t = 100 (For truck)

We need to find r2.

Statement 1 says it took the car 30 minutes to travel half of the distance
=> 1 hour to travel the entire distance
=> t = 1 hour

Hence, r2 x 1 = 100
=> r2 = 100 m/hr

Sufficient.

Statement 2 says that the average speed of the truck was ten
miles per hour less than the average speed of the car.

Rate x Time = Distance
r1 x t = 120 (For Sports car)
r2 x t = 100 (For truck)

Given, r2 = r1 - 10
Hence,
r1 x t = 120 (For Sports car)
(r1 - 10) x t = 100 (For truck)

Solving we get t = 2 hours
Hence, r2 x 2 = 100 (for truck)
=> r2 = 50

I was not sure if I was solving this correctly since I am getting different values for r2 in I and II. Can you please assist?

Thanks,
Sri
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Data Sufficiency |
User avatar
Legendary Member
Posts: 1556
Joined: Tue Aug 14, 2012 11:18 pmFollowed by: 34 members
Thanked: 448 times
GMAT Score:650

by theCodeToGMAT » Mon Dec 23, 2013 11:23 pm
Time of Sports Car = Time of Truck
120/S = 100/T
T/S = 5/6 -(1)

To find: T

Statement 1:
Distance = 60
Time = 0.5 hours
Speed for first Half = 60/0.5
BUT, we have no info about total time
INSUFFiCIENT

Statement 2:
T = S - 10
S = T+10
using in (1)
T/(T+10) = 5/6
We can solve and get "T"
SUFFICIENT
Answer [spoiler]{B}[/spoiler]
R A H U L
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 641
Joined: Tue Feb 14, 2012 3:52 pmFollowed by: 8 members
Thanked: 11 times

by gmattesttaker2 » Mon Dec 23, 2013 11:54 pm
theCodeToGMAT wrote:Time of Sports Car = Time of Truck
120/S = 100/T
T/S = 5/6 -(1)

To find: T

Statement 1:
Distance = 60
Time = 0.5 hours
Speed for first Half = 60/0.5
BUT, we have no info about total time
INSUFFiCIENT

Statement 2:
T = S - 10
S = T+10
using in (1)
T/(T+10) = 5/6
We can solve and get "T"
SUFFICIENT
Answer [spoiler]{B}[/spoiler]

Hi,

Thanks for your reply. I had the following question about Statement I.

Since rate is 60/0.5 miles/hour and distance is 120 miles, cannot we not calculate the time ?

Thanks,
Sri
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Legendary Member
Posts: 1556
Joined: Tue Aug 14, 2012 11:18 pmFollowed by: 34 members
Thanked: 448 times
GMAT Score:650

by theCodeToGMAT » Tue Dec 24, 2013 12:24 am
gmattesttaker2 wrote: Hi,

Thanks for your reply. I had the following question about Statement I.

Since rate is 60/0.5 miles/hour and distance is 120 miles, cannot we not calculate the time ?

Thanks,
Sri
If we solve 60/0.5 = 120.. then we get the speed for the first half distance but we don't know, for the rest half distance, the time Truck/Car consumed; we cannot extrapolate to conclude that for rest half also it took 30 minutes..
That's why Statement 1 is Insufficient.
R A H U L
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
GMAT Instructor
Posts: 3225
Joined: Tue Jan 08, 2008 2:40 pmFollowed by: 614 members
Location: Toronto
Thanked: 1710 times
GMAT Score:800

by Stuart@KaplanGMAT » Tue Dec 24, 2013 12:32 am
Sri wrote:Hi,

Thanks for your reply. I had the following question about Statement I.

Since rate is 60/0.5 miles/hour and distance is 120 miles, cannot we not calculate the time ?

Thanks,
Sri
Hi Sri!

You've assumed that the car's speed is constant - which is exactly what the question is designed to trick you into assuming!

Remember: on the GMAT we only know what we're explicitly told. Since we don't know whether the car is travelling at a constant speed, there's no way we can determine how long the other half of the trip took it.

Here's the good news - you fell for the trap in practice, so you won't fall for it on the actual test!

Stuart
Image

Stuart Kovinsky | Kaplan GMAT Faculty | Toronto

Kaplan Exclusive: The Official Test Day Experience | Ready to Take a Free Practice Test? | Kaplan/Beat the GMAT Member Discount
BTG100 for $100 off a full course
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 641
Joined: Tue Feb 14, 2012 3:52 pmFollowed by: 8 members
Thanked: 11 times

by gmattesttaker2 » Tue Dec 24, 2013 10:47 am
theCodeToGMAT wrote:
gmattesttaker2 wrote: Hi,

Thanks for your reply. I had the following question about Statement I.

Since rate is 60/0.5 miles/hour and distance is 120 miles, cannot we not calculate the time ?

Thanks,
Sri
If we solve 60/0.5 = 120.. then we get the speed for the first half distance but we don't know, for the rest half distance, the time Truck/Car consumed; we cannot extrapolate to conclude that for rest half also it took 30 minutes..
That's why Statement 1 is Insufficient.

Hello,

Thank you very much for clarifying.

Best Regards,
Sri
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 641
Joined: Tue Feb 14, 2012 3:52 pmFollowed by: 8 members
Thanked: 11 times

by gmattesttaker2 » Tue Dec 24, 2013 10:58 am
Stuart Kovinsky wrote:
Sri wrote:Hi,

Thanks for your reply. I had the following question about Statement I.

Since rate is 60/0.5 miles/hour and distance is 120 miles, cannot we not calculate the time ?

Thanks,
Sri
Hi Sri!

You've assumed that the car's speed is constant - which is exactly what the question is designed to trick you into assuming!

Remember: on the GMAT we only know what we're explicitly told. Since we don't know whether the car is travelling at a constant speed, there's no way we can determine how long the other half of the trip took it.

Here's the good news - you fell for the trap in practice, so you won't fall for it on the actual test!

Stuart

Hello Stuart,

Thank you very much for clarifying and for the tip.

Best Regards,
Sri
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1