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If it is true that z < 8 and 2z > -4, which of the fol

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If it is true that z < 8 and 2z > -4, which of the fol

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If it is true that z < 8 and 2z > -4, which of the following must be true?

A. -8 < z < 4
B. z > 2
C. z > -8
D. z < 4
E. None of the above

The OA is C.

Can I say, z < 8 and 2z < -4 = z < -2, then -2 < z < 8, right?

Only C is always true, as ANY z from the TRUE range, -2 < z < 8, will be greater than -8.

Experts, any suggestion about this PS question? Thanks in advance.

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LUANDATO wrote:
If it is true that z < 8 and 2z > -4, which of the following must be true?

A. -8 < z < 4
B. z > 2
C. z > -8
D. z < 4
E. None of the above

The OA is C.

Can I say, z < 8 and 2z < -4 = z < -2, then -2 < z < 8, right?

Only C is always true, as ANY z from the TRUE range, -2 < z < 8, will be greater than -8.

Experts, any suggestion about this PS question? Thanks in advance.
I would have set it up the same way you did. You are correct in saying that -2 < Z < 8. Further you are correct in saying that C is true. Every possible value of Z is greater than -8.

A) doesn't hold --> test z = 5
B) doesn't hold --> test z = 1
D) doesn't hold --> test z = 5

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LUANDATO wrote:
If it is true that z < 8 and 2z > -4, which of the following must be true?

A. -8 < z < 4
B. z > 2
C. z > -8
D. z < 4
E. None of the above

The OA is C.

Can I say, z < 8 and 2z < -4 = z < -2, then -2 < z < 8, right?

Only C is always true, as ANY z from the TRUE range, -2 < z < 8, will be greater than -8.

Experts, any suggestion about this PS question? Thanks in advance.
Hi LUANDATO,

Your conclusion, -2 < z < 8, is perfect.
So, if z is BETWEEN -2 and 8, then z must be greater than -8

Answer: C

Cheers,
Brent

_________________
Brent Hanneson – Creator of GMATPrepNow.com
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LUANDATO wrote:
If it is true that z < 8 and 2z > -4, which of the following must be true?

A. -8 < z < 4
B. z > 2
C. z > -8
D. z < 4
E. None of the above

The OA is C.

Can I say, z < 8 and 2z < -4 = z < -2, then -2 < z < 8, right?

Only C is always true, as ANY z from the TRUE range, -2 < z < 8, will be greater than -8.

Experts, any suggestion about this PS question? Thanks in advance.
Hi LUANDATO,

Your conclusion, -2 < z < 8, is perfect.
So, if z is BETWEEN -2 and 8, then z must be greater than -8

Answer: C

Cheers,
Brent

_________________
Brent Hanneson – Creator of GMATPrepNow.com
Use our video course along with Beat The GMAT's free 60-Day Study Guide

Sign up for our free Question of the Day emails
And check out all of our free resources

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