BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

What is the summation of the maximum and the

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
Elite Legendary Member
Posts: 3991
Joined: Fri Jul 24, 2015 2:28 am
Location: Las Vegas, USA
Thanked: 19 times
Followed by:37 members

What is the summation of the maximum and the

by Max@Math Revolution » Tue Apr 07, 2020 3:21 am

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

[GMAT math practice question]

What is the summation of the maximum and the minimum values of 6x - 37?

1) x satisfies 2 < \(\sqrt{3\left(x-4\right)}\) ≤ 5.
2) x is an integer.
Top
Source: — Data Sufficiency |
User avatar
Elite Legendary Member
Posts: 3991
Joined: Fri Jul 24, 2015 2:28 am
Location: Las Vegas, USA
Thanked: 19 times
Followed by:37 members

Re: What is the summation of the maximum and the

by Max@Math Revolution » Thu Apr 09, 2020 6:03 pm

Timer

00:00

Your Answer

A

B

C

D

E

Global Stats

=>

Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution.
Visit https://www.mathrevolution.com/gmat/lesson for details.

Since we have 1 variable (x) and 0 equations, D is most likely the answer. So, we should consider each condition on its own first.

Condition 1)

2 < \(\sqrt{3\left(x-4\right)}\) ≤ 5
=> 4 < 3(x - 4) ≤ 25 (squaring)
=> 4/3 < x - 4 ≤ 25/3 (dividing by 3)
=> 16/3 < x ≤ 37/3 (adding 4)

Then even though x has a maximum value, x doesn’t have a minimum value.

Since condition 1) does not yield a unique solution, it is not sufficient.

Condition 2)

Since condition 2) does not yield a unique solution; obviously, it is not sufficient.

Conditions 1) & 2)

Since we have 16/3 < x ≤ 37/3 from condition 1), the possible values of x are 6, 7, 8, …, 12.
Then the maximum and minimum values of x are 6 and 12, respectively.
Thus, their sum is 6 + 12 = 18.

Since both conditions together yield a unique solution, they are sufficient.

Therefore, C is the answer.
Answer: C


If the original condition includes “1 variable”, or “2 variables and 1 equation”, or “3 variables and 2 equations,” etc., one more equation is required to answer the question. If each of conditions 1) and 2) provide an additional equation, there is a 59% chance that D is the answer, a 38% chance that A or B is the answer, and a 3% chance that the answer is C or E. Thus, answer D (conditions 1) and 2), when applied separately, are sufficient to answer the question) is most likely, but there may be cases where the answer is A, B, C, or E.
Top
Post new topic Post Reply
• Page 1 of 1