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rfulky
04-30-2008, 05:00 PM
How many prime numbers are there strictly greater than 5 and less than integer k?

(1) 20 < k < 34

(2) 17 < k < 33

The answer is E (Statements (1) and (2) TOGETHER are NOT sufficient).

I don't understand why. To me for each statement alone you can determine how many prime numbers are between 5 and K.

example (my way of thinking)

Statement (1)
K=23,

Therefore, between 5 and 23 there are 5 prime number (7,11,13,17,19)

With this information I can determine how many prime numbers are between 5 and any integer k.

Where am I going wrong?
Thanks for all your help!

kevin
05-01-2008, 04:09 PM
We are told that k is an integer, but not that k is a prime number.

Kevin Armstrong
Manhattan Review