Data Sufficiency

Hi

I have problems with three questions. This is the second of three related posts. I would appreciate your help in any! Thanks.

I'm having some difficulties understanding Q144 of the Official Guide 11 in Data Sufficiency (page 335).
Question goes something like this:
144. If n is a positive integer, is (1/10)^n < 0.01 ?
(i) n > 2
(ii) (1/10)^(n-1) < 0.1
The correct answer is supposedly D [each statement alone is sufficient]

statement (i) is not a problem. I get it why it is sufficient.
statement (ii), however, is said to be sufficient because we can determine that the expression holds true for n>2.

Nonetheless, I would have said insufficient, because there are two values of n (n=1, 2), for which the expression is false and no information is given that these values are excluded. We therefore, in my reasoning, have insufficient information as it holds true in some cases, and holds false in others.

Can someone expain the OG reasoning please?

Thanks!

take 10^(n-1) to RHS and you will come to know why n > 2...

baguette82 wrote:Hi

I have problems with three questions. This is the second of three related posts. I would appreciate your help in any! Thanks.

I'm having some difficulties understanding Q144 of the Official Guide 11 in Data Sufficiency (page 335).
Question goes something like this:
144. If n is a positive integer, is (1/10)^n < 0.01 ?
(i) n > 2
(ii) (1/10)^(n-1) < 0.1
The correct answer is supposedly D [each statement alone is sufficient]

statement (i) is not a problem. I get it why it is sufficient.
statement (ii), however, is said to be sufficient because we can determine that the expression holds true for n>2.

Nonetheless, I would have said insufficient, because there are two values of n (n=1, 2), for which the expression is false and no information is given that these values are excluded. We therefore, in my reasoning, have insufficient information as it holds true in some cases, and holds false in others.

Can someone expain the OG reasoning please?

Thanks!

Rewrite the question:

Is (1/10)^n < (1/10)^2?

Or more simply: Is n>2?

Statement 1:
Tell us outright that n>2. Sufficient.

Statement 2:
If (1/10)^(n-1) < 1/10, the smallest positive integer that works is n=3:
(1/10)^(3-1) < 1/10
(1/10)^2 < 1/10
1/100 < 1/10
So n>2. Sufficient.

The correct answer is D.