A is a sequence such that each term is 2 more than the

Question

A is a sequence such that each term is 2 more than the preceeding term. What is the third term of A?
I) The middle term of A is 26
II) The sum of the first and last terms is 52

MA · Answer

another good question............
Hmmmm.. simple but confusing. 

i think OA is E.

from i, it is not suff....

from, it is also not suff.
sum of A1+An=52, we donot know how many terms are there 3,4,5,6,7,8 ............................

even with combining i and ii, we do not know how many terms are there in the series A.

series An could be or => 24,26,28 or => 22,24,26,28,30.
in first case third term is 28, where as in second case the third term is 26.

both series meet the conditions mentioned in i and ii but are not suff to ans.

HongHu · Answer

Good one. I almost said D. Somehow the mention of third, middle and first and last gave me an impression that there were only three terms in the series. But I realize now that it is a trap.

(E) it is.

MA · Answer

i was also about to do the same. but later realized from ii that last is not third...

nocilis · Answer

I choose C as the answer, but I think the problem is wrong as 1) and 2) contradict each other.
Series: X, X+2, X+4, X+6 , ... X + 2(n-1) 
 where X is the first term and the last term above is the n th term

I) Middle term is 26:
The series has to have odd number of numbers to have a middle term. So n is odd and middle term = X+ 2*((n+1)/2 -1) =26

=> X+ n = 27

Can't really solve with just this.

II) The sum of the first and last terms is 52
Assuming last term is the nth term

X + X + 2(n-1) = 52
=> X +n = 25
Can't really solve with just this.

I) and II together, contradict each other.

When I tried to solve this first of course, I did not do the above calculations, but simply assumed that if we have two equations with X and n, we can solve it so I picked C.

The OA was E. but Seems like the problem is wrong as we have contradicting statements.

Comments?

FN · Answer

I was about to say D as well....at least you guys caught it....

good one!

banerjeea_98 · Answer

Nocilis, u can't solve for X and N using the eqn u got, even tho u have 2 eqn. I guess at that point u can say that ans can't be determined, hence "E". I got this one wrong, I went with "C", thinking the numbers r 24,26,28 :wall

nocilis · Answer

Although E is the most acceptable answer, the Statements I and II are contradicting as the resulting equations together are not mathematically valid for real numbers. This one is from UpstartRaising GMAT simulator CAT exam 3. I hope ETS won't give statements that contradict!

HongHu · Answer

You miscaculated this one. (I) and (II) do not give contradictory conclusions.

nocilis · Answer

Damn ...
Yes a miscalculation.
I and II are essentially saying the same thing.

This GMAT thing is driving me nuts!!

A is a sequence such that each term is 2 more than the

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