alexBLR wrote:
Ten years ago, scientists predicted that the animal z would become extinct in t years. What is t?
(1) Animal z became extinct 4 years ago.
(2) If the scientists had extended their extinction prediction for animal z by 3 years, their prediction would have been incorrect by 2 years.
From S1 we learn that the animal became extinct 6 years after the scientists made their prediction. Of course, we have no info about t, so this is not sufficient. Similarly S2 is not sufficient, since we have no info about when the animal actually became extinct.
Combining the two Statements, we know that if we add three to t, the value we get will be two away from the correct value, which is, from Statement 1, six. We do not, however, know if it will be two above or two below the correct value, so we will get two different possible values for t. That is, the scientists may have predicted the animal would become extinct in 1 year; adding three, we are off by two from the correct value of 6. Or, they may have predicted the animal would become extinct in 5 years; again, adding three, we are off by two from the correct value of 6. The answer is E.
I'm curious where the question is from; it's a bit different from other questions I've seen.
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