Copper pipe costs $x$ cents per foot in $8$-foot lengths, and $x + y$ cents per foot in shorter lengths. What is

Expert replies

Previous Topic Next Topic

M7MBA: Moderator; Posts: 2058; Joined: Sun Oct 29, 2017 4:24 amFollowed by: 5 members; Thanked: 1 times

by M7MBA » Thu Oct 29, 2020 12:46 pm

Timer

00:00

Your answer

Difficulty–

right wrong

Pick an answer to see how members did

Copper pipe costs $x$ cents per foot in $8$-foot lengths, and $x + y$ cents per foot in shorter lengths. What is the lowest possible price, in cents, of $51$ feet of pipe in terms of $x$ and $y?$

A. $51(x + y)$
B. $51x$
C. $48x + 3y$
D. $48(x + y)$
E. $51x + 3y$

Answer: E

Source: Princeton Review

Source: Beat The GMAT — Problem Solving | Thu Oct 29, 2020 12:46 pm

swerve: Legendary Member; Posts: 2604; Joined: Sun Oct 29, 2017 2:04 pmFollowed by: 6 members

Re: Copper pipe costs $x$ cents per foot in $8$-foot lengths, and $x + y$ cents per foot in shorter lengths. What

by swerve » Fri Oct 30, 2020 5:53 am

M7MBA wrote: ↑
Thu Oct 29, 2020 12:46 pm
Copper pipe costs $x$ cents per foot in $8$-foot lengths, and $x + y$ cents per foot in shorter lengths. What is the lowest possible price, in cents, of $51$ feet of pipe in terms of $x$ and $y?$

A. $51(x + y)$
B. $51x$
C. $48x + 3y$
D. $48(x + y)$
E. $51x + 3y$

Answer: E

Source: Princeton Review

$51=8 \cdot 6 + 3$

So we need $6$ bars of $8$-foot length, which costs $48x$ and $3$-foot shorter bars, which costs $3(x+y)$

$48x+3(x+y)=51x+3y\Longrightarrow$ E

jhavyom: Junior | Next Rank: 30 Posts; Posts: 16; Joined: Fri Oct 02, 2020 9:16 am

Re: Copper pipe costs $x$ cents per foot in $8$-foot lengths, and $x + y$ cents per foot in shorter lengths. What

by jhavyom » Sun Nov 01, 2020 12:33 am

M7MBA wrote: ↑
Thu Oct 29, 2020 12:46 pm
Copper pipe costs $x$ cents per foot in $8$-foot lengths, and $x + y$ cents per foot in shorter lengths. What is the lowest possible price, in cents, of $51$ feet of pipe in terms of $x$ and $y?$

A. $51(x + y)$
B. $51x$
C. $48x + 3y$
D. $48(x + y)$
E. $51x + 3y$

Answer: E

Source: Princeton Review

51 foot = 48 foot + 3 foot
Since 48 is a multiple of 8, price for 48 foot = 48x
Now, price for remaining 3 foot, 3(x+y)

Total cost = 48x + 3(x+y) = 51x + 3y

Choice E is the answer.

GMAT/MBA Expert

Scott@TargetTestPrep: GMAT Instructor; Posts: 8246; Joined: Sat Apr 25, 2015 10:56 amFollowed by: 29 members; Location: Los Angeles, CA; Thanked: 43 times

Re: Copper pipe costs $x$ cents per foot in $8$-foot lengths, and $x + y$ cents per foot in shorter lengths. What

by Scott@TargetTestPrep » Thu Nov 05, 2020 2:39 pm

M7MBA wrote: ↑
Thu Oct 29, 2020 12:46 pm
Copper pipe costs $x$ cents per foot in $8$-foot lengths, and $x + y$ cents per foot in shorter lengths. What is the lowest possible price, in cents, of $51$ feet of pipe in terms of $x$ and $y?$

A. $51(x + y)$
B. $51x$
C. $48x + 3y$
D. $48(x + y)$
E. $51x + 3y$

Answer: E

Solution:

For 51 feet of pipe, the cheapest option is to buy six 8-foot pipes and one 3-foot pipe. Therefore, the lowest possible price, in cents, of 51 feet of pipe, is:

6 * 8 * x + 1 * 3 * (x + y) = 48x + 3x + 3y = 51x + 3y

Answer: E

Scott Woodbury-Stewart
Founder and CEO
[email protected]

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

Featured schoolRound 2 closes Jan 7, 2027 54 days left

Chicago Booth

Since 1982, 10 Booth faculty members have received the Nobel Prize in Economic Sciences, more than any other business school.

#3
U.S. News rank: $175,000
Median base salary: 670
Average GMAT Focus: 635
Students in the class

Apply to Booth Visit chicagobooth.edu See the full profile

Photo: Warren LeMay, CC BY-SA 2.0

GMAT Course Reviews

563 reviews

1168 reviews

431 reviews

359 reviews

147 reviews

5/5

5 Star (563 Reviews)

"Target Test Prep is the closest to the official version of the GMAT exam, about 99% accuracy in terms of the quality and quantity of information. The course has excellently created singular sets of focused lessons and tests for every possible topic that one could come across in the official GMAT exam."

"The TTP course maximizes the efficiency of the time you spend studying. It will take time and effort but I could almost guarantee that if you complete the course exactly as it is laid out you will get an amazing score. They also have a very responsive team willing to help with any questions you might have."

"TTP has two things that I think no other test prep company offers: A teaching approach that reinforces understanding and an attitude that will give you the mental preparedness needed to succeed on the test. TTP gives you a deep understanding of the concept you need to know while teaching you how to think."

Write a Review