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

Redeem

The ‘moving walkway’ is a 300-foot long conveyor . . .

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Moderator
Posts: 2058
Joined: Sun Oct 29, 2017 4:24 am
Thanked: 1 times
Followed by:5 members

The ‘moving walkway’ is a 300-foot long conveyor . . .

by M7MBA » Sat Dec 30, 2017 7:32 am

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

The 'moving walkway' is a 300-foot long conveyor belt that moves continuously at 3 feet per second. When Bill steps on the walkway, a group of people that are also on the walkway stands 120 feet in front of him. He walks toward the group at a combined rate (including both walkway and foot speed) of 6 feet per second, reaches the group of people, and then remains stationary until the walkway ends. What is Bill's average rate of movement for his trip along the moving walkway?

A) 2 feet per second
B) 2.5 feet per second
C) 3 feet per second
D) 4 feet per second
E) 5 feet per second

The OA is the option E.

I didn't know how to solve this PS question. Experts, may you help me? What is the equation I should use?
Top
Source: — Problem Solving |
User avatar
GMAT Instructor
Posts: 555
Joined: Wed Oct 04, 2017 4:18 pm
Thanked: 180 times
Followed by:12 members

by EconomistGMATTutor » Mon Jan 01, 2018 9:40 am
The 'moving walkway' is a 300-foot long conveyor belt that moves continuously at 3 feet per second. When Bill steps on the walkway, a group of people that are also on the walkway stands 120 feet in front of him. He walks toward the group at a combined rate (including both walkway and foot speed) of 6 feet per second, reaches the group of people, and then remains stationary until the walkway ends. What is Bill's average rate of movement for his trip along the moving walkway?

A) 2 feet per second
B) 2.5 feet per second
C) 3 feet per second
D) 4 feet per second
E) 5 feet per second

The OA is the option E.

I didn't know how to solve this PS question. Experts, may you help me? What is the equation I should use?
Hi M7MBA,
Let's take a look at your question.

Time Bill takes to reach the group = Distance / Speed = 120/6 = 20 sec
During these 20 seconds the group of people covered some distance at a speed of belt i.e. 3 feet per second. To calculate that distance:
Distance = Speed * Time
Distance = 3 * 20 = 60 feet

Now, we can calculate the remaining distance to cover on the moving walk away.
Remaining distance = 300 - 120 - 60 = 120 feet

Time taken to cover the last 120 feet at 3 feet per second (because every remains stationary)
Time = Distance / Speed = 120/3 = 40 sec

Total Distance = 300 feet
Total Time spent = 20 + 40 = 60 sec

Now we can find Bill's average rate of movement using formula:
Average rate of movement = Total Distance / Total Time
Average rate of movement = 300/60 = 5 feet per second

Therefore, Option E is correct.

Hope it helps.
I am available if you'd like any follow up.
GMAT Prep From The Economist
We offer 70+ point score improvement money back guarantee.
Our average student improves 98 points.

Image
Top

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 8086
Joined: Sat Apr 25, 2015 10:56 am
Location: Los Angeles, CA
Thanked: 43 times
Followed by:29 members

by Scott@TargetTestPrep » Sat Aug 24, 2019 4:21 am
M7MBA wrote:The 'moving walkway' is a 300-foot long conveyor belt that moves continuously at 3 feet per second. When Bill steps on the walkway, a group of people that are also on the walkway stands 120 feet in front of him. He walks toward the group at a combined rate (including both walkway and foot speed) of 6 feet per second, reaches the group of people, and then remains stationary until the walkway ends. What is Bill's average rate of movement for his trip along the moving walkway?

A) 2 feet per second
B) 2.5 feet per second
C) 3 feet per second
D) 4 feet per second
E) 5 feet per second

The OA is the option E.

I didn't know how to solve this PS question. Experts, may you help me? What is the equation I should use?

We are given that Bill catches up to a group of people and then remains stationary until the walkway ends. Let's determine the time, t, needed to catch up to the group of people who are 120 feet ahead of him.

Since Bill is moving at a rate of 6 ft/sec (walkway speed plus Bill's foot speed), his distance is 6t. Since the group of people is moving at 3 ft/sec (walkway speed only) and the group is 120 feet ahead, the group's distance is 3t + 120. When Bill catches up to the group, the two distances are equal. Thus, we can create the following equation and determine t:

6t = 3t + 120

3t = 120

t = 40

Therefore, it takes him 40 seconds to catch up to the group. During this 40-second period, he moves 6 x 40 = 240 feet. Since the walkway is 300 ft long, he has 300 - 240 = 60 feet remaining. However, since he is stationary after he catches up to the group, he is moving only at the walkway speed, which is 3 ft/sec. Therefore, in the last 60 feet, it takes 60/3 = 20 seconds to complete the distance, and thus it takes him a total of 40 + 20 = 60 seconds to complete the walkway from one end to another.

Since average speed = total distance/total time, his average speed = 300/60 = 5 ft/sec.

Answer: E

Scott Woodbury-Stewart
Founder and CEO
[email protected]

Image

See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews

ImageImage
Top
Post new topic Post Reply
• Page 1 of 1