For each positive integer n, the integer n* is defined by n* = n^2 + 1. What is the value of the positive integer k ?
(1) when k is divided by 4, the reminder is 1.
(2) 18<k*<36
In statement '2' 18 is less than or equal to k* and K* is less than or equal 36. I didn't found that symbol, sorry for that.
Thank You...
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Data sufficiency
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- Uva@90
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Hi,Newaz111 wrote:For each positive integer n, the integer n* is defined by n* = n^2 + 1. What is the value of the positive integer k ?
(1) when k is divided by 4, the reminder is 1.
(2) 18<k*<36
In statement '2' 18 is less than or equal to k* and K* is less than or equal 36. I didn't found that symbol, sorry for that.
Thank You...
[/spoiler][/url]
Is OA B ?
Please post OA along with Question.
Here is how I did,
Stmt 1: 5 and 9 are two possible values of K.hence insufficient.
Stmt 2:
18<= k^2+1 <= 36
Substitute values for K
K =4 ==> K^2 +1 = 17 hence not possible.
K =5 ==> K^2+1 = 26 YES possible.
K =6 ==> K^2+1 = 37 not possible.
Hence K = 5
Sufficient.
So OA is B
Regards,
Uva.
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Target question: What is the value of the positive integer k?Newaz111 wrote:For each positive integer n, the integer n* is defined by n* = n² + 1. What is the value of the positive integer k ?
(1) When k is divided by 4, the reminder is 1.
(2) 18 < k* < 36
Statement 1: When k is divided by 4, the reminder is 1.
There are MANY MANY possible values of k that satisfy statement 1.
Some possible values of k include 1, 5, 9, 13, etc
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: 18 < k* < 36
Let's examine some possible values of k* by testing some positive integers.
1* = 1² + 1 = 2 [not within the range of 18 < k* < 36]
2* = 2² + 1 = 5 [not within the range of 18 < k* < 36]
3* = 3² + 1 = 10 [not within the range of 18 < k* < 36]
4* = 4² + 1 = 17 [not within the range of 18 < k* < 36]
5* = 5² + 1 = 26 [WITHIN the range of 18 < k* < 36]
6* = 6² + 1 = 37 [not within the range of 18 < k* < 36]
7* = 7² + 1 = 50 [not within the range of 18 < k* < 36]
If 18 < k* < 36, then we can see that k must equal 5
Since we can answer the target question with certainty, statement 2 is SUFFICIENT
Answer = B
Cheers,
Brent