In question it is given that for first minute--> one ques in 2 seconds---> 30 ques per min
for second min rate --> 1 ques in 1.5 seconds--> 40 ques per min
for third minute--> 1 ques per second -->60 ques per min
toal ques in 3 min = 130.

And Ques asks min ques right in 3rd minute.

(1) Danjie’s previous high score was reached by answering all the questions given in the first three minutes and getting 90% of them correct.

this gives number of total right ans = 117. so, new highest score will be 118(atleast). now if we want to calculate minimum right ques in 3rd minute to reach new highest score we will have to consider first 100% correct answers in first 2 minutes. so, this will give 70(first 2 minutes) + 48(3rd minute). Sufficient

(2) If Danjie does not answer 100% of the questions correctly during the first minute and during the second minute, the game will not continue.
This fails to provide exact number needed to reach new highest score.Insufficient.

So, (A). Hope it helps.

Hi Ankit,

100% in first two minutes is necessary because we are asked to calculate minimum right answers to reach new highest score.

in A we have been given a limit that is 117. and ques is providing that we need to cross this limit by getting minimum right answers in 3rd minute.

Hope it is clear now.

I don't think this question makes much logical sense, and you certainly won't find any analogous questions on the real GMAT. A DS question generally can't ask for minimum or maximum values of things, because then the question will usually be confusing necessary and sufficient conditions. So as Visshu explained above, using Statement 1 it will be necessary for Danjie to answer at least 48 questions correctly in the third minute to beat her high score, but that won't be sufficient for her to beat her score - she would also need to answer 100% of her other questions correctly. This is a Data Sufficiency question, after all, so it should be asking about sufficiency. The wording of the question itself also makes it sound as though Danjie is in the middle of a game, and has completed the first two minutes and is about to begin the third minute. That is clearly not the intended meaning when you read the statements, however.

So I don't think the setup makes sense, for one thing. For another, we learn from Statement 2 that there are additional conditions built into the game that aren't explained in the stem. I don't find that a fair way to present information in a DS question - if we don't even know how the game works from the stem, how can we answer any questions about it? Finally, the question asks about how she might beat her 'high score', but the stem nowhere explains how the game is scored. I suppose we're meant to understand that each equation is worth one point, but when the questions in the third minute need to be answered more quickly than those in the first, and when Statement 2 opens up the possibility that there are rules built into this game that the question has not described, I think it's reasonable to wonder if we have enough information about how the game is scored to answer any kind of question here.

So I think it's just a poorly devised question overall, and I would ignore it. If the answer is indeed A, then the whole setup is just a really complicated way of asking "how many questions did Danjie get right on her best try at this game?" and with that interpretation, it's a very low-level question.
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