Twenty-five sets of problems on Data Interpretation

Question

Twenty-five sets of problems on Data Interpretation -- one each for the DI sections of 25 CATALYST tests -- were prepared by the AMS research team. The DI section of each CATALYST contained 50 questions of which exactly 35 questions were unique, i.e., they had not been used in the DI section of any of the other 24 CATALYSTs. 
What could be the maximum possible number of questions prepared of the DI sections of all the 25 CATALYSTs put together?

A) 1,100

B) 975

C) 1,070

D) 1,055

Source: Tata McGraw-Hill: CAT

magbot · Answer

There is no E choice ? Why ?

generis · Answer

magbot  , occasionally questions from original sources do not include five answer choices.

amascarenhas · Answer

I didn´t reach the exact value, but I was rather close to the solution I believe to be right.

Exactly 35 questions in each set are unique, so we have 25*35 =875 unique questions
we want to maximize the repeated question, so we will assume that the questions are repeated twice.

If the questions were not repeated then we would have 15*25=375 additional questions, but as the questions are repeated at least twice, we will have ay most half of the questions. Nevertheless the value is odd and not even, so we must assume that one of the questions will be repeated 3 times.

the result should be 875+1+(375-3)/2 = 1062
With answer question C we would have more than 35 unique questions in each set, so the closest answer would be A.

Twenty-five sets of problems on Data Interpretation

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