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 Starts Oct 17
Chris Peckover, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Chris Peckover, 100th-Percentile GMAT Scorer

Oct 17 · Chris Peckover
Sat · 11:00 AM to 2:00 PM ET
Oct 20 · Chris Peckover
Tue, Thu · 8:00 to 10:00 PM ET
Oct 25 · Josh Braslow
Sun · 1:00 to 4:00 PM ET
Included
40 hours of live online classes + 6 months of TTP OnDemand
  • Attend the first class for free
  • Every class is recorded, so you never fall behind
View classes & enroll
Limited seats availableTarget Test Prep
EALiveTeachOnDemand 5 seats left Start anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

Logan Thompson
EXECUTIVE ASSESSMENT

Sep 6 to Dec 6, 2026

with Logan Thompson

165+ EA score guarantee
$05-day trial no automatic billing
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 Start free 5-day trial
Limited cohort · enrollment openTrial includes full course accessTarget 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.

what is the value of A

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 313
Joined: Tue Oct 13, 2015 7:01 am
Thanked: 2 times
by jain2016 » Mon Apr 18, 2016 10:17 am
The integers A, B, C, and D shown on the number line above are all equally spaced. If C and D are equal to 5 12 and 5 13, respectively, what is the value of A?

A) 5^ 11
B) 5^ 10
C) -5^ 12
D) (-7)5^ 12
E) (-12)5^ 13

OAD
Attachments
line.gif
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
User avatar
Legendary Member
Posts: 2663
Joined: Wed Jan 14, 2015 8:25 amFollowed by: 128 members
Location: Boston, MA
Thanked: 1153 times
GMAT Score:770

by DavidG@VeritasPrep » Mon Apr 18, 2016 10:36 am
jain2016 wrote:The integers A, B, C, and D shown on the number line above are all equally spaced. If C and D are equal to 5^12 and 5^13, respectively, what is the value of A?

A) 5^ 11
B) 5^ 10
C) -5^ 12
D) (-7)5^ 12
E) (-12)5^ 13

OAD
I believe the question should have had C = 5^12 and D = 5^13.

Let's call the distance of each segment: x. So the distance between A and B is x, and the distance between B and C is x, etc. So the gap between A and C is 2x, meaning that A = 5^12 -2x.

Now we need to solve for x. If the distance between D and C is x, then we set x = 5^13 - 5^12.
Factor out 5^12, so that 5^13 - 5^12 = 5^12(5 - 1) = 5^12 * 4.

If x = (5^12) * 4, and A = 5^12 - 2x, then A = 5^12 - 2[(5^12) * 4] = 5^12 - (5^12)*8 = (5^12)(1 - 8) = (5^12)*(-7)

Answer is D
Veritas Prep | GMAT Instructor

Veritas Prep Reviews
Save $100 off any live Veritas Prep GMAT Course
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 2095
Joined: Tue Dec 04, 2012 3:22 pmFollowed by: 247 members
Thanked: 1443 times

by ceilidh.erickson » Mon Apr 18, 2016 12:45 pm
David's explanation is perfect, and that's really the only way to solve this one. I just want to add (since I was talking about this problem with a student a few days ago)...

If you ever get an answer on the GMAT that feels way too easy, it probably is!

A shocking number of students pick 5^10 on this one, even though they think "huh, it's probably too easy to go 12 - 1 - 1." Trust that instinct! Any answer that you can get to by doing just 1 or 2 pieces of simple arithmetic can't be the answer. The GMAT is never that nice! Ask yourself - what's the twist in this problem that I missed?

On this problem, it's "equally spaced." Consecutive powers (for any base other than 0, 1, or -1) will never be evenly spaced, so it can't be as simple as just subtracting exponents.
Ceilidh Erickson
EdM in Mind, Brain, and Education
Harvard Graduate School of Education
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
GMAT Instructor
Posts: 15539
Joined: Tue May 25, 2010 12:04 pmFollowed by: 1906 members
Location: New York, NY
Thanked: 13060 times
GMAT Score:790

by GMATGuruNY » Mon Apr 18, 2016 1:22 pm
jain2016 wrote:The integers A, B, C, and D shown on the number line above are all equally spaced. If C and D are equal to 5¹² and 5¹³, respectively, what is the value of A?

A) 5¹¹
B) 5¹�
C) -5¹²
D) (-7)5¹²
E) (-12)5¹³

OAD
The length of each space = CD.

Since A is 3 spaces to the left of D, we get:
A = D - (3)(CD)

= 5¹³ - 3(5¹³ - 5¹²)

= 5¹³ - 3(5¹³) + 3(5¹²)

= -2(5¹³) + 3(5¹²)

= 5¹²(-2*5 + 3)

= 5¹²(-7).

The correct answer is D.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 16207
Joined: Mon Dec 08, 2008 6:26 pmFollowed by: 1268 members
Location: Vancouver, BC
Thanked: 5254 times
GMAT Score:770

by Brent@GMATPrepNow » Mon Apr 18, 2016 1:45 pm
Here are two similar questions to practice with:
- https://www.beatthegmat.com/evenly-space ... 63714.html
- https://www.beatthegmat.com/challenge-2- ... 67201.html

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
Image
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1