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
GMATBootcamp Starts Sep 28
Chris Peckover, Target Test Prep GMAT expert
LIVE ONLINE BOOTCAMP

Live Online Bootcamp Class with Top GMAT Expert Chris Peckover

15 live classes from Sep 28, 2026

Schedule
Mon to Fri · 7:00 to 10:00 PM ET
Included
Live classes + 6 months of TTP OnDemand
  • Boost your GMAT score in less than one month in a live online class
  • 6 months access to TTP OnDemand video courses included
View bootcamp & enroll
Limited cohort · enrollment openTarget Test Prep
EALiveTeach 5 seats left
Logan Thompson
EXECUTIVE ASSESSMENT

Sep 6 to Dec 6, 2026

with Logan Thompson

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
Limited cohort · enrollment openTarget 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.

Fixed cost & variable cost. Confusing answer?

Expert replies
by suyashps » Tue Feb 10, 2009 11:34 am
Here is that confusing question:

The total cost of producing item A is equal to the sum of item A's fixed cost and variable cost. If the variable cost of producing A decreased by 10% in last month, by what percent did the total cost of producing item A change in last month?

(1) The fixed cost of producing item A increased by 15% in last month.

(2) Before the changes in last month, the fixed cost of producing item A was 5 times the variable cost of producing item A.

This is a question similar to what I encountered in one of the MGMAT practice CAT. Changed variable name and numbers. Dont know if that violets any IP rights. Anyways, according to them the correct answer is C - both together.

I say B i.e. 2 is sufficient. Because to calculate total cost with information in (2) we can assume that fixed cost has NOT changed (it is called at FIXED COST after all!). The answer explanation says we cannot count on (2) because WE DON'T KNOW CHANGE IN THE FIXED COST. But why should we assume any change in fixed cost? Dont we ignore (1) while evaluating option (2) independently? I am confused :(

What should be the right answer?
Join the discussion
Source: — Data Sufficiency |

by dmateer25 » Tue Feb 10, 2009 11:52 am
You can't assume that the fixed costs didn't change.

This question is a classic example of when you should use the information from statement 1 to your advantage when looking at statement 2. Since you know that on the GMAT the 2 statement won't contradict each other.

If statement one says that the fixed costs changed then you can make a general assumption that the fixed costs changed.

Now when looking at statement 2 you only know that the variable costs changed, but you don't know about the fixed costs. (but from statement one we know the fixed costs changed so you can't assume that they stayed the same). Therefore, statement 2 is insufficient.

You need both statements together to solve this question.
Join the discussion

by suyashps » Thu Feb 12, 2009 11:14 am
dmateer25 wrote: Since you know that on the GMAT the 2 statement won't contradict each other.
Wow, Never knew that! :shock:
Join the discussion