If k not equal to 0, 1, or -1, is 1/k >0?
stmt A. 1/k-1 > 0
stmt B. 1/k+1 > 0
The answer is Stmt A.
Can someone explain why stmt B is not sufficent?
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- Guest
Hi, Please see my explanation below -
Given questions :
If k not equal to 0, 1, or -1, is 1/k >0?
stmt A. 1/k-1 > 0
stmt B. 1/k+1 > 0
Let us take statement I - In this, it is given that 1/(k-1) >0. This implies that k must be postive and k must be greater than 1. Hence, 1/k is definitely greater than zero. For example, k's value is 2, then 1/(2-1) = 1 which is > 0. This implies that 1/2 = 0.5 which si still greater than '0'. Hence, this is sufficient.
Let us take II - It says 1/ (k+1) > 0 which means that this will satisfy for both positive and negative values of k which are less than -1. for example, if k is 2, 1/(k+1) is >0 and 1/k wll be >0. But if k's value is -0.5, it will satisfy the second equation but 1/k will be -2 which is <0 and hence, INSUFFICIENT.
Hence, A alone is sufficient to answer this question.
Hope this helps.
Given questions :
If k not equal to 0, 1, or -1, is 1/k >0?
stmt A. 1/k-1 > 0
stmt B. 1/k+1 > 0
Let us take statement I - In this, it is given that 1/(k-1) >0. This implies that k must be postive and k must be greater than 1. Hence, 1/k is definitely greater than zero. For example, k's value is 2, then 1/(2-1) = 1 which is > 0. This implies that 1/2 = 0.5 which si still greater than '0'. Hence, this is sufficient.
Let us take II - It says 1/ (k+1) > 0 which means that this will satisfy for both positive and negative values of k which are less than -1. for example, if k is 2, 1/(k+1) is >0 and 1/k wll be >0. But if k's value is -0.5, it will satisfy the second equation but 1/k will be -2 which is <0 and hence, INSUFFICIENT.
Hence, A alone is sufficient to answer this question.
Hope this helps.
- RonPurewal
- Students
- Posts: 19744
- Joined: Tue Aug 14, 2007 8:23 am
good explanation.
you made a false substitution of one word (corrected below in red) - it's a rather important word, which is why i'm posting a correction.
otherwise, perfect.
you made a false substitution of one word (corrected below in red) - it's a rather important word, which is why i'm posting a correction.
otherwise, perfect.
Anonymous Wrote:Hi, Please see my explanation below -
Given questions :
If k not equal to 0, 1, or -1, is 1/k >0?
stmt A. 1/k-1 > 0
stmt B. 1/k+1 > 0
Let us take statement I - In this, it is given that 1/(k-1) >0. This implies that k must be postive and k must be greater than 1. Hence, 1/k is definitely greater than zero. For example, k's value is 2, then 1/(2-1) = 1 which is > 0. This implies that 1/2 = 0.5 which si still greater than '0'. Hence, this is sufficient.
Let us take II - It says 1/ (k+1) > 0 which means that this will satisfy for both positive and negative values of k which are greater than -1. for example, if k is 2, 1/(k+1) is >0 and 1/k wll be >0. But if k's value is -0.5, it will satisfy the second equation but 1/k will be -2 which is <0 and hence, INSUFFICIENT.
Hence, A alone is sufficient to answer this question.
Hope this helps.
4 posts Page 1 of 1