If n denotes a number left of the 0 on the number line such that n is less than 1/100 when squared, then the reciprical must be?
a. less than than -10
b. between -1 and -1/10
c. between -1/10 and 0
d. between 0 and 1/10
e. greater than 10
Answer is a. Care to explain?
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Night reader
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very easy question if you know the mode properties and can operate with the values on a number lineGHong14 wrote:If n denotes a number left of the 0 on the number line such that n is less than 1/100 when squared, then the reciprical must be?
a. less than than -10
b. between -1 and -1/10
c. between -1/10 and 0
d. between 0 and 1/10
e. greater than 10
Answer is a. Care to explain?
|n|^2 < 1/100
|n| < 1/10
condition precedent - n denotes a number left of the 0 on the number line
hence n < -1/10, the reciprocal of any number is [ 1 / number ], 1/n = -10
Select A.
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junegmat221
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Well for this question its best to assume .
Start with N ^2 < 0.01
Equate to some number square of a number which also has integer roots.
So, N^2 can be equal to -(0.04). Because N is left of 0 in the number line.
Now Take square root of N which is will be equal to -(0.2) which is essentially -(2/10).
And the Reciprocal of -(2/10) is -(10/2) which is equal to -5.
Now recheck with the choices.
Only A should be valid since -5 is lesser than -10.
Hope it helps ..
Start with N ^2 < 0.01
Equate to some number square of a number which also has integer roots.
So, N^2 can be equal to -(0.04). Because N is left of 0 in the number line.
Now Take square root of N which is will be equal to -(0.2) which is essentially -(2/10).
And the Reciprocal of -(2/10) is -(10/2) which is equal to -5.
Now recheck with the choices.
Only A should be valid since -5 is lesser than -10.
Hope it helps ..
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GMATGuruNY
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The easiest approach is to plug in a value that satisfies the conditions in the problem.GHong14 wrote:If n denotes a number left of the 0 on the number line such that n is less than 1/100 when squared, then the reciprical must be?
a. less than than -10
b. between -1 and -1/10
c. between -1/10 and 0
d. between 0 and 1/10
e. greater than 10
Answer is a. Care to explain?
Let n = -(1/100). This works because (-1/100)^2 = 1/10000, and 1/10000 < 1/100.
1/n = -100.
Since -100 < -10, the correct answer is A.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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