Trinomial Question

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Trinomial Question

by Kaunteya » Fri Feb 29, 2008 5:18 pm
What is the value of v^3 – k^3?
(1) vk > 0
(2) v – k = 6

A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.

I am going to have to go with E.
I can't for the life of me find a good was to simply v^3 - k^3. Maybe someone knows how to do it. Otherwise I think I am right in saying that neither the statements help in solving this question.

Cheers and Good Luck everyone
Kaunteya

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Re: Trinomial Question

by Stuart@KaplanGMAT » Fri Feb 29, 2008 6:35 pm
Kaunteya wrote:What is the value of v^3 – k^3?
(1) vk > 0
(2) v – k = 6

A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.

I am going to have to go with E.
I can't for the life of me find a good was to simply v^3 - k^3. Maybe someone knows how to do it. Otherwise I think I am right in saying that neither the statements help in solving this question.

Cheers and Good Luck everyone
Kaunteya
Don't have to simplify, just pick some easy numbers.

(1) both positive or both negative - nothing about values, insufficient.

(2) they're 6 apart. Well, v=100 and k=94 would certainly give us a different answer than v=7 and k=1: insufficient.

Even togther, we could pick the same pairs of numbers we did in statement (2): still insufficient, choose (E)
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