If n denotes a number to the left of zero on the number line such that the square of n is less than 1/100, then the reciprocal of n must be:
1)less than -10
2)between -1 and -1/10
3)between -1/10 and 0
4)between 0 and 1/10
5)greater than 10
Thanks in advance for your answers. The answer is B.
gmat prep
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Darn. I didn't read the question properly! Yes it is B. <Edited my previous Post>
If n^2 < 1/100 then,
-1/10 < n < 1/10. Calculating the reciprocal,
the equation will be,
-10 < 1/n > 10. How? Consider a similar equation:
-1/2 < 1/4 < 1/2. Here n = 1/4. Calculate the reciprocal:
-2 < 4 > 2.
But, n is less than zero and so 1/n will also be less than 0. So the equation becomes,
-10 < 1/n (Reciprocal of n) < 0.
Also, n value will is between 0 and -1/10. So any value between 0 and -1 will have a reciprocal with value less than -1. Hence,
-10 < 1/n < -1.
If n^2 < 1/100 then,
-1/10 < n < 1/10. Calculating the reciprocal,
the equation will be,
-10 < 1/n > 10. How? Consider a similar equation:
-1/2 < 1/4 < 1/2. Here n = 1/4. Calculate the reciprocal:
-2 < 4 > 2.
But, n is less than zero and so 1/n will also be less than 0. So the equation becomes,
-10 < 1/n (Reciprocal of n) < 0.
Also, n value will is between 0 and -1/10. So any value between 0 and -1 will have a reciprocal with value less than -1. Hence,
-10 < 1/n < -1.
Last edited by enniguy on Mon Sep 07, 2009 3:20 am, edited 3 times in total.
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Question states that n is left of zero on the number line. So n is negative. D and E are ruled out
Next part states that its square is less than 1/100...
1/400 is less than 1/100. Its negative root would be -1/20
Reciprocal of -1/20 is -20 which is less than -10
Answer has to be A
Next part states that its square is less than 1/100...
1/400 is less than 1/100. Its negative root would be -1/20
Reciprocal of -1/20 is -20 which is less than -10
Answer has to be A