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 Author: Gennadiy [ Tue Nov 02, 2010 4:39 am ] Post subject: Re: math (test 1, question 35): data sufficiency, inequaliti The statement (1) implies that x ≤ 3.If x = 8/3 then 8x = 16 + 2x.If x = 0 then 8x ≠ 16 + 2x.Therefore the statement (1) is NOT sufficient by itself.Be careful not to confuse which statement should follow and which one is given."If x = 8/3 then x ≤ 3" is TRUE."If x ≤ 3 then x = 8/3" is clearly NOT TRUE.In the question the statement x ≤ 3 is given as the statement (1) and the statement x = 8/3 should be examined.

 Author: questioner [ Sat Feb 05, 2011 3:10 pm ] Post subject: Re: math (test 1, question 35): data sufficiency, inequaliti That would never happen on the GMAT. Part (i) and Part (ii) never contradict each other. This is misleading.

Author:  Gennadiy [ Sat Feb 05, 2011 4:14 pm ]
Post subject:  Re: math (test 1, question 35): data sufficiency, inequaliti

Like in many other data sufficiency questions:
- each statement alone defines a possible range of values;
- the both statements combined result in the intersection of those ranges;
- if all the elements in the intersection answer the statement question identically, then the both statements combined are sufficient.

(1) -3x is greater than or equal to -9
x ≤ 3
Tells us that the possible values of x are:

(2) 2x is greater than or equal to 6
x ≥ 3
Tells us that the possible values of x are:

When we combine the both statements the range of possible values is just one point:

In similar questions this intersection could be some other range, like 1 < x < 2 or -1 < x ≤ 0, etc.