What is the value of the integer x? (1) 8

Question

What is the value of the integer x? 

(1) 8 < x^3 < 64
(2) 4 < x^2 < 16


answer and explain

salr15 · Answer

D.

(1) 8 < x^3 < 64

if x = 2; 2^3 = 8 
 x = 3; 3^3 = 27 
 x = 4; 4^3 = 64

Suff only x = 3 works.

(2) 4 < x^2 < 16

x = 2; x^2 = 4
x = 3; x^2 = 9
x = 4; x^2 = 16 

again, only 3 works.

Suff

dahcrap · Answer

Since x is an integer, x^2 and x^3 have to be integers. So I feel it is D unless there is some superb trick here

Himalayan · Answer

the trick in B is that x could be -3 or 3.

lanter1 · Answer

Himalayan is correct. Always be on the lookout for negative numbers and ther number zero when doing DS

Mishari · Answer

I would got with A and here is my explanation:

(1) 8 < x^3 < 64 
----------------------
cube root of 64 is 4 and the cube root of 8 is 2. X has to be 3. 

statement 1 is sufficient


(2) 4 < x^2 < 16 
--------------------
Similarly, x can be either -3 or +3, both of which would result in a value for x^2 of 9.

statement 2 is insufficient


 ANSWER:   A

What is the value of the integer x? (1) 8 < x^3 < 64

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