All computers manufactured after 1998 have a minimum

Question

All computers manufactured after 1998 have a minimum processing speed of 400 MHz. My computer has a processing speed of 399 MHz.

Which of the following can definitely NOT be concluded from the above statements?

I) My computer was definitely manufactured after 1998.
II) My computer may have been manufactured in 1998.
III) If it had been manufactured a year later, my computer would have had a faster processing speed.

(A) I only
(B) II only
(C) III only
(D) I and III only
(E) II and III only

I don't agree with the OA... I'll see what other people come up with. Someone please let me know if this problem has already been posted elsewhere.

Minheequang · Answer

All computers manufactured after 1998 have a minimum processing speed of 400 MHz. My computer has a processing speed of 399 MHz.

Which of the following can definitely NOT be concluded from the above statements?

I) My computer was definitely manufactured after 1998 -->  surely wrong 
II) My computer may have been manufactured in 1998 -->  It states "may have been", not "must have been", so it's true 
III) If it had been manufactured a year later, my computer would have had a faster processing speed --> who know for sure ? Besides, which year was it manufactured ? hence, wrong

(A) I only
(B) II only
(C) III only
(D) I and III only -->  best 
(E) II and III only

snatekar · Answer

All computers manufactured after 1998 have a minimum processing speed of 400 MHz. My computer has a processing speed of 399 MHz.

Which of the following can definitely NOT be concluded from the above statements?

I) My computer was definitely manufactured after 1998 --> surely wrong

II) My computer may have been manufactured in 1998  --> Cannot be definitely concluded whether it was manufactured in 98. This option can definitely NOT be concluded.

III) If it had been manufactured a year later, my computer would have had a faster processing speed.  --> This cannot be concluded, since the manufacturing year of my computer relative to 1998 is unknown. If it had been known that my computer was manufactured in 1998, then this could have surely been concluded. Hence this too cannot be concluded DEFINITELY from the above statement. Hence only I can be surely concluded as NOT TRUE. Hence option A seems correct.

wondering · Answer

IMO D, as I is definitely NOT CONCLUDED and for III we cannot be sure as his computer need not necessarily have faster processing speed had it been manufactured a year later.

GMATaddict · Answer

The OA is indeed "D", although I remain somewhat skeptical.

How do you guys define "definitely NOT be concluded"?

I originally interpreted it as "you can be 100% sure this conclusion is incorrect". In other words, if I'm unsure whether a conclusion is correct/incorrect, then that would not fit into the category of "definitely NOT be concluded".

Following that interpretation, I knew that (I) is definitely wrong; (II) is not definitely wrong; and (III) is ALSO not definitely wrong, since we're not sure when exactly the PC was manufactured.

Therefore, since II & III can be right or wrong (depending on the year of manufacture), so we cannot conclude that these two conclusions can "definitely NOT be concluded", and (I) is the only conclusion that fits into that category.

As a result, my personal answer was "A", but apparently I am distorting the phrase somehow. Someone please help me correctly define this phrase.

ngoctraiden1905 · Answer

I choose A, I only
III is not so clear: one year later but the question does not let's know the present time. If the present time is 1990 then computer made in 1991 was not necessary faster than computer made in 1990. Am I wrong somewhere?

gmattokyo · Answer

I would have gone with (A)
(D) could have been true... i mean can't be ruled out DEFINITELY. there is possibility that my PC was manufactured in 1998

11MBA · Answer

This is a tricky one. At first glance it looks like D, but I think A is actually the correct answer.

Since the question asks for what can definitely NOT be concluded. III is actually possible so it cannot be completely ruled out. Only I can be ruled out for sure.

What's the OA?

All computers manufactured after 1998 have a minimum

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