If k is a positive integer and has exactly two digits, what is k?
(1) The sum of the digits is 3.
(2) k is odd.
Which is the sufficient statement?
OA C
If k is a positive integer
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We go into this question knowing that k is a positive integer with exactly two digits.
Statement 1
If the sum of the digits is 3, we only have a couple options for what the digits could be: 0 and 3 or 1 and 2. What numbers can we make with these digits?
03 --> NOT two digits
30
12
21
Based on Statement 1 alone, there are three options for k. Not sufficient.
Statement 2
If k is odd, k can be any odd number from 11 and 99. Not sufficient.
Both
Looking at our three options from Statement 1 (30, 12, 21), we can eliminate 30 and 12 for being even. 21 is the only odd option, so k must be 21. Sufficient.
Statement 1
If the sum of the digits is 3, we only have a couple options for what the digits could be: 0 and 3 or 1 and 2. What numbers can we make with these digits?
03 --> NOT two digits
30
12
21
Based on Statement 1 alone, there are three options for k. Not sufficient.
Statement 2
If k is odd, k can be any odd number from 11 and 99. Not sufficient.
Both
Looking at our three options from Statement 1 (30, 12, 21), we can eliminate 30 and 12 for being even. 21 is the only odd option, so k must be 21. Sufficient.
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Hi lehannie07,
We're told that K is a positive integer and has EXACTLY two digits. We're asked for the value of K. This question can be solved by TESTing VALUES.
1) The sum of the digits of K is 3.
Since K has exactly 2 digits, K could be 12, 21 or 30.
Fact 1 is INSUFFICIENT
2) K is ODD.
Since K has exactly 2 digits, K could be 11, 13, 15, or any other odd 2-digit number.
Fact 2 is INSUFFICIENT
Combined, we know:
-The sum of the digits of K is 3.
-K is ODD.
The only value that 'fits' both of the Facts is 21.
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
We're told that K is a positive integer and has EXACTLY two digits. We're asked for the value of K. This question can be solved by TESTing VALUES.
1) The sum of the digits of K is 3.
Since K has exactly 2 digits, K could be 12, 21 or 30.
Fact 1 is INSUFFICIENT
2) K is ODD.
Since K has exactly 2 digits, K could be 11, 13, 15, or any other odd 2-digit number.
Fact 2 is INSUFFICIENT
Combined, we know:
-The sum of the digits of K is 3.
-K is ODD.
The only value that 'fits' both of the Facts is 21.
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
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We are given that k is a positive integer and has exactly two digits, and we need to determine the value of k.lheiannie07 wrote:If k is a positive integer and has exactly two digits, what is k?
(1) The sum of the digits is 3.
(2) k is odd.
Statement One Alone:
The sum of the digits is 3.
k could be equal to either 21, 12, or 30. Statement one alone is not sufficient to answer the question.
Statement Two Alone:
k is odd.
k could be 11 or 13 or some other two-digit odd number. The information in statement two is not sufficient to answer the question.
Statements One and Two Together:
Using both statements, since the sum of k's two digits is 3 and k is odd, k must be 21.
Answer: C
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