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

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

Triangle ABC has a perimeter of 18. Which of the following

Expert replies
by M7MBA » Sun Feb 11, 2018 3:54 am
Triangle ABC has a perimeter of 18. Which of the following cannot be the area of triangle ABC?

(A) 119/359
(B) 359/119
(C) π
(D) 12
(E) 16

The OA is the option E.

Experts, how can I solve this PS question? How can I know which one is the correct answer? Can you show me how would you solve it?

Thanks in advanced.
Join the discussion
Source: — Problem Solving |

by GMATGuruNY » Sun Feb 11, 2018 4:13 am
M7MBA wrote:Triangle ABC has a perimeter of 18. Which of the following cannot be the area of triangle ABC?

(A) 119/359
(B) 359/119
(C) π
(D) 12
(E) 16
Given a FIXED PERIMETER for a triangle, the greatest possible are will be yielded if the triangle is EQUILATERAL.

The area of an equilateral triangle = (s²/4)√3.
√3 ≈ 1.7.

If a triangle with a fixed perimeter of 12 is equilateral -- implying that each side has a length of 4 -- we get:
Greatest possible area = (s²/4)√3 = (4²/4)√3 = 9√3 ≈ (9()(1.7) = 15.3.
Thus, the area cannot be equal to 16.

The correct answer is E.

A similar rule:
Given a quadrilateral with a fixed perimeter, the greatest possible area will be yielded if the quadrilateral is a SQUARE.
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
Join the discussion

by [email protected] » Sun Feb 11, 2018 11:30 am
Hi M7MBA,

We're told that a triangle has a perimeter of 18. We're asked which of the following CANNOT be the area of the triangle. This question can be solved with a little logic, by TESTing VALUES and using the answer choices to our advantage.

To start, we could make LOTS of different triangles with a perimeter of 18 (keep in mind that the side lengths do NOT need to be integers) and some of the triangles would be so 'long and thin' that their areas would be almost 0. Thus, "fractional" areas are possible. Thus, we have to start thinking in terms of how big the area could get. Logically-speaking, there WILL be a maximum area, so it's likely that the answer to this question is the biggest answer. There is a way to prove it though...

Imagine if we had a 45/45/90 right triangle with sides of 5, 5 and 5√2. Since √2 = about 1.4, the perimeter of this triangle would be a little less than 18. The area of THIS triangle would be (1/2)(5)(5) = 12.5, o a slightly larger triangle would have a slightly larger area. Thus, any area less than, or equal to, 12.5 is possible. Four of the answers fit that range - and one of them does not....

Final Answer: E

GMAT assassins aren't born, they're made,
Rich
Contact Rich at [email protected]
Image
Join the discussion