• NEW! FREE Beat The GMAT Quizzes
Hundreds of Questions Highly Detailed Reporting Expert Explanations
• 7 CATs FREE!
If you earn 100 Forum Points

Engage in the Beat The GMAT forums to earn
100 points for $49 worth of Veritas practice GMATs FREE VERITAS PRACTICE GMAT EXAMS Earn 10 Points Per Post Earn 10 Points Per Thanks Earn 10 Points Per Upvote ## The toll for crossing a certain bridge is$0.75...

tagged by: BTGmoderatorLU

## The toll for crossing a certain bridge is $0.75... The toll for crossing a certain bridge is$0.75 each crossing. Drivers who frequently use the bridge may instead purchase a sticker each month for $13.00 and then pay only$0.30 each crossing during that month. If a particular driver will cross the bridge twice on each of x days next month and will not cross the bridge on any other day, what is the least value of x for which this driver can save money by using the sticker?

A. 14
B. 15
C. 16
D. 28
E. 29

The OA is B.

I'm really confused with this PS question. Experts, any suggestion about how to solve it? Thanks in advance.

### GMAT/MBA Expert

Legendary Member
Joined
14 Jan 2015
Posted:
2667 messages
Followed by:
122 members
1153
GMAT Score:
770
LUANDATO wrote:
The toll for crossing a certain bridge is $0.75 each crossing. Drivers who frequently use the bridge may instead purchase a sticker each month for$13.00 and then pay only $0.30 each crossing during that month. If a particular driver will cross the bridge twice on each of x days next month and will not cross the bridge on any other day, what is the least value of x for which this driver can save money by using the sticker? A. 14 B. 15 C. 16 D. 28 E. 29 The OA is B. I'm really confused with this PS question. Experts, any suggestion about how to solve it? Thanks in advance. Cost not using the sticker: number of crossings = 2x. Cost per crossing:$.75. Total cost = 2x * .75 = 1.50x

Cost using the sticker: Cost per crossing: $.30. Number of crossings: 2x. Cost for crossings: .30*2x = .60x. But there's a$13 fee, so the total cost for this option is 13 + .60x.

Break-even point: 1.50x = 13 + .60x
.90x = 13
x = 13/.9 = 130/9 = 14 4/9.

If the break-even point is a little greater than 14, then the sticker begins saving the user money at 15 days. The answer is B

_________________
Veritas Prep | GMAT Instructor

Veritas Prep Reviews
Save $100 off any live Veritas Prep GMAT Course Enroll in a Veritas Prep GMAT class completely for FREE. Wondering if a GMAT course is right for you? Attend the first class session of an actual GMAT course, either in-person or live online, and see for yourself why so many students choose to work with Veritas Prep. Find a class now! ### GMAT/MBA Expert Legendary Member Joined 14 Jan 2015 Posted: 2667 messages Followed by: 122 members Upvotes: 1153 GMAT Score: 770 LUANDATO wrote: The toll for crossing a certain bridge is$0.75 each crossing. Drivers who frequently use the bridge may instead purchase a sticker each month for $13.00 and then pay only$0.30 each crossing during that month. If a particular driver will cross the bridge twice on each of x days next month and will not cross the bridge on any other day, what is the least value of x for which this driver can save money by using the sticker?

A. 14
B. 15
C. 16
D. 28
E. 29

The OA is B.

I'm really confused with this PS question. Experts, any suggestion about how to solve it? Thanks in advance.
Alternative approach. If you see that the driver will spend $1.50 on crossing days without the sticker and$.60 on crossing days with the sticker, then we see that she's saving $.90 on each crossing day. So the question becomes: For how many days must she save$.90 until she's made up for that $13 fee. Now back solve. A: If she save$.90 on each of 14 days, she'll save .9*14 = $12.60. Not enough to offset the$13 fee.

But we know we'll save an additional $.90 on the 15th day, bringing the total savings to 12.60 + .90 --> clearly more than 13. So the answer is B _________________ Veritas Prep | GMAT Instructor Veritas Prep Reviews Save$100 off any live Veritas Prep GMAT Course

Enroll in a Veritas Prep GMAT class completely for FREE. Wondering if a GMAT course is right for you? Attend the first class session of an actual GMAT course, either in-person or live online, and see for yourself why so many students choose to work with Veritas Prep. Find a class now!

### GMAT/MBA Expert

GMAT Instructor
Joined
09 Apr 2015
Posted:
1465 messages
Followed by:
18 members
39
LUANDATO wrote:
The toll for crossing a certain bridge is $0.75 each crossing. Drivers who frequently use the bridge may instead purchase a sticker each month for$13.00 and then pay only $0.30 each crossing during that month. If a particular driver will cross the bridge twice on each of x days next month and will not cross the bridge on any other day, what is the least value of x for which this driver can save money by using the sticker? A. 14 B. 15 C. 16 D. 28 E. 29 We can create the following inequality: 0.75(2x) > 13 + 0.3(2x) 1.5x > 13 + 0.6x 0.9x > 13 x > 13/0.9 x > 130/9 x > 14 4/9 So the minimum value of x is 15. Answer: B _________________ Jeffrey Miller Head of GMAT Instruction jeff@targettestprep.com See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews • Free Veritas GMAT Class Experience Lesson 1 Live Free Available with Beat the GMAT members only code • Get 300+ Practice Questions 25 Video lessons and 6 Webinars for FREE Available with Beat the GMAT members only code • Magoosh Study with Magoosh GMAT prep Available with Beat the GMAT members only code • FREE GMAT Exam Know how you'd score today for$0

Available with Beat the GMAT members only code

• 5-Day Free Trial
5-day free, full-access trial TTP Quant

Available with Beat the GMAT members only code

• Free Practice Test & Review
How would you score if you took the GMAT

Available with Beat the GMAT members only code

• Free Trial & Practice Exam
BEAT THE GMAT EXCLUSIVE

Available with Beat the GMAT members only code

• Award-winning private GMAT tutoring
Register now and save up to \$200

Available with Beat the GMAT members only code

• 1 Hour Free
BEAT THE GMAT EXCLUSIVE

Available with Beat the GMAT members only code

• 5 Day FREE Trial
Study Smarter, Not Harder

Available with Beat the GMAT members only code

### Top First Responders*

1 Ian Stewart 57 first replies
2 Jay@ManhattanReview 29 first replies
3 Brent@GMATPrepNow 29 first replies
4 GMATGuruNY 20 first replies
5 ceilidh.erickson 15 first replies
* Only counts replies to topics started in last 30 days
See More Top Beat The GMAT Members

### Most Active Experts

1 Scott@TargetTestPrep

Target Test Prep

211 posts
2 Max@Math Revolution

Math Revolution

92 posts
3 Brent@GMATPrepNow

GMAT Prep Now Teacher

68 posts
4 Ian Stewart

GMATiX Teacher

65 posts
5 GMATGuruNY

The Princeton Review Teacher

39 posts
See More Top Beat The GMAT Experts