Problems on sequence Part I (for bacali and others)

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by cramya » Thu Nov 27, 2008 3:25 pm
Is it C) 1/10

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austin wrote:The sum of 1/91, 1/92, 1/93, ...1/100 cannot less than which of the following numbers?
1/8 1/9 1/10 1/11 1/12
This can't be a real question, since we can answer it with 100% certainty without doing any work at all. The answer MUST be (e), the smallest choice.

Let's just think about it logically:

If the answer COULD NOT be less than 1/8, then it also COULD NOT be less than the 4 smaller numbers, giving us 5 correct answers to the question.

If the answer COULD NOT be less than 1/9, then it also COULD NOT be less than the 3 smaller numbers, giving us 4 correct answers to the question.

If the answer COULD NOT be less than 1/10, then it also COULD NOT be less than the 2 smaller numbers, giving us 3 correct answers to the question.

If the answer COULD NOT be less than 1/11, then it also COULD NOT be less than the 1 smaller number, giving us 2 correct answers to the question.

Therefore, the answer must be (E), because that's the only choice that will lead to 1 and only 1 correct answer.

Note: I haven't actually done the math, so it's possible that there IS more than 1 correct answer, which just means that there is no correct answer to the question.
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by cramya » Thu Nov 27, 2008 3:38 pm
Stuart,
Thanks!

When I choose C) its should have struck me to choose E) since if it cant be less than C) it cant be leas than E)

Like u said there are mutiple correct answers to the question which ic an see now

Thanks again!