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If 18 < x < 68, is the integer x even?
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09 Mar 2016, 13:06
Question Stats:
51% (01:07) correct 49% (01:24) wrong based on 55 sessions
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If 18 < x < 68, is the integer x even?
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Updated on: 09 Mar 2016, 15:22
According to how i went on solving this, i got the answer as C.
1) neither units nor tens digit is prime.
=> it is composite => possible numbers for both  4,6,8,9 which will give numbers such as 44, 46, 48, 49  here you get both even and odd => not sufficient
2) Sum of tens and units digit is prime => possible tens digit nos  1,2,3,4,5,6, possible units digit nos 1,2,3,5,6,7,8,9,0
=> some of the numbers are  20,21,25,29,32 ..  here again you get both even and odd => not sufficient
1)+2) => possible number for tens and units places  4,6 possible number for units places  4,6,8,9 sum of tens and units digits is prime => will give only one answer 13 (49; 4+9 =13) odd => x is not even
Answer: C
Originally posted by PSV01 on 09 Mar 2016, 13:24.
Last edited by PSV01 on 09 Mar 2016, 15:22, edited 1 time in total.



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If 18 < x < 68, is the integer x even?
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Updated on: 12 Mar 2016, 10:17
Bunuel wrote: If 18 < x < 68, is the integer x even?
(1) Neither the tens digit nor the units digits of x is prime. (2) Sum of the tens digit and units digit of x is prime. I was able to do this in half a minute but took me 15 minutes to try to write down the thinking process. Writing confused me Will give writing a shot nevertheless Tens can be 2,3,4,5,6 Units can be anything from 0 to 9 plus number 19 Statement 1 Forget 10s digit, the units digit can be 1,4,6,8,9 clearly, x can be odd or ever Not sufficient Statement 2Prime sum options 21,23,25,32 etc Since these are both odd and even numbers Not sufficient Together realising that 2 can not be the units digit (since it is prime) 4,6,or 8 in units will sum up to prime numbers only when ten's digit is prime. So can't be. Possible values 19,41,49,61 Only Odd Hence C Correction in the posted Question  Neither the tens digit nor the units digit s of x is prime.
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Re: If 18 < x < 68, is the integer x even?
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09 Mar 2016, 15:13
KarishmaParmar Though you have arrived at the same answer like me Don't forget that 1 is neither prime nor composite



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Re: If 18 < x < 68, is the integer x even?
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06 Oct 2017, 23:40
PSV01 wrote: KarishmaParmar Though you have arrived at the same answer like me Don't forget that 1 is neither prime nor composite The question says the number is not prime. It does not say that the number is not composite. Hence 1 should be included.



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Re: If 18 < x < 68, is the integer x even?
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06 Oct 2017, 23:41
KarishmaParmar wrote: Bunuel wrote: If 18 < x < 68, is the integer x even?
(1) Neither the tens digit nor the units digits of x is prime. (2) Sum of the tens digit and units digit of x is prime. I was able to do this in half a minute but took me 15 minutes to try to write down the thinking process. Writing confused me Will give writing a shot nevertheless Tens can be 2,3,4,5,6 Units can be anything from 0 to 9 plus number 19 Statement 1 Forget 10s digit, the units digit can be 1,4,6,8,9 clearly, x can be odd or ever Not sufficient Statement 2Prime sum options 21,23,25,32 etc Since these are both odd and even numbers Not sufficient Together realising that 2 can not be the units digit (since it is prime) 4,6,or 8 in units will sum up to prime numbers only when ten's digit is prime. So can't be. Possible values 19,41,49,61 19 should not be included here. 10 is not a prime. Only Odd Hence C Correction in the posted Question  Neither the tens digit nor the units digit s of x is prime.




Re: If 18 < x < 68, is the integer x even? &nbs
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06 Oct 2017, 23:41






