Is b greater than 1?

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Is b greater than 1?

by [email protected] » Fri Aug 10, 2012 7:08 pm
Q Is b greater than 1?

(1) b^2 is greater than b

(2) b is positive

Correct Answer: Together (C).

I am leaning towards (E). Can you explain in detail why C is the correct answer and the strategy behind it. I would really appreciate the help!

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by Anurag@Gurome » Fri Aug 10, 2012 7:17 pm
[email protected] wrote:Q Is b greater than 1?

(1) b^2 is greater than b

(2) b is positive

Correct Answer: Together (C).

I am leaning towards (E). Can you explain in detail why C is the correct answer and the strategy behind it. I would really appreciate the help!
(1) b² > b.
b(b - 1) > 0 implies b < 0 or b > 1
Hence, b may or may not be greater than 1; NOT sufficient.

(2) b is positive implies b > 0.
Hence, b may or may not be greater than 1; NOT sufficient.

Combining (1) and (2), clearly b > 1; SUFFICIENT.

The correct answer is C.
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by vk_vinayak » Sat Aug 11, 2012 9:14 am
[email protected] wrote:Q Is b greater than 1?

(1) b^2 is greater than b

(2) b is positive

Correct Answer: Together (C).

I am leaning towards (E). Can you explain in detail why C is the correct answer and the strategy behind it. I would really appreciate the help!
1) If b=2, then b^2 > b, and if b=-2, then also b^2 > b. Insufficient.
2) If b=0.5 the b^2 < b, and if b=2, then b^2 > b. Insufficient.

Combining 1 and 2, We can say for sure that b>1. Sufficient.
(For any number b such that 0<b<1, then b^2 < b, and if b=1, then b^2 = b. Therefore if b is +ve and b^2 > b, then b has to be greater than 1)
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by [email protected] » Sun Aug 12, 2012 2:13 pm
Thank you, Anurag.
Anurag@Gurome wrote:
[email protected] wrote:Q Is b greater than 1?

(1) b^2 is greater than b

(2) b is positive

Correct Answer: Together (C).

I am leaning towards (E). Can you explain in detail why C is the correct answer and the strategy behind it. I would really appreciate the help!
(1) b² > b.
b(b - 1) > 0 implies b < 0 or b > 1
Hence, b may or may not be greater than 1; NOT sufficient.

(2) b is positive implies b > 0.
Hence, b may or may not be greater than 1; NOT sufficient.

Combining (1) and (2), clearly b > 1; SUFFICIENT.

The correct answer is C.