How many prime integers are less than the integer x? (1)

Question

How many prime integers are less than the integer x?

(1) 11<X<19

(2)17<=x<=29

hardworker_indian · Answer

E?

In all three cases - Stat(I), Stat(II), Both - the count is different when x=17 than when x=18.

gmat800 · Answer

Mine is E too...different for 17,18

chunjuwu · Answer

let me clarify it, combine (1) with (2)

the scope will be 17<=x<19

so, x might be 17 or 18

Therefore, the number of prime integers less than x will be different, 

2,3,5,7,11,13, 17  or 2,3,5,7,11,13

is it right? 

thank you

dushver · Answer

The question seeks to find prime number lesser than X.
It is therefore first to determine X.

I worked with the similar logic as yours and got E as the answer. 
Because X can't be uniquely determined (as you showed, the number of primes vary with the 17 and 18). The answer is therefore E.

rahul · Answer

my bad instead of looking X as integer i took x as prime too .

thanks folks , i know my mistake i agree with you folks its E.

How many prime integers are less than the integer x? (1)

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