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Inequalities Problem

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Inequalities Problem

by jeffboshine » Sat Mar 31, 2012 2:54 pm
If zt < -3, is Z<4?

I) Z<9
II) t<-4


I came up with B as answer. That was wrong. The answer is E.

If T<-4, Then Z > 1/2 (if Z = -6) and Z > 1/10 (if Z = -30). Wouldn't that make II sufficient?
Source: — Data Sufficiency |

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by Bill@VeritasPrep » Sat Mar 31, 2012 3:01 pm
In statement 2, t could be -5 and z could be 6, which gives you a product of -30 and an answer of no, z is not less than 4.

T could be -5 and z could be 2, which gives you a product of -10 and an answer of yes, z is greater than 4.

Since we can get a yes and a no, it is insufficient.

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by Anurag@Gurome » Sun Apr 01, 2012 9:15 pm
jeffboshine wrote:If zt < -3, is Z<4?

I) Z<9
II) t<-4


I came up with B as answer. That was wrong. The answer is E.

If T<-4, Then Z > 1/2 (if Z = -6) and Z > 1/10 (if Z = -30). Wouldn't that make II sufficient?
If zt < -3, is z < 4?

(1) z < 9
If z = 5, t = -5, then zt = -25, which is < -3. Here z > 4.
If z = 3, t = -5, then zt = -15, which is < -3. Here z < 4.
No definite answer; NOT sufficient.

(2) t < -4, taking the same examples in statement 1.
If z = 5, t = -5, then zt = -25, which is < -3. Here z > 4.
If z = 3, t = -5, then zt = -15, which is < -3. Here z < 4.
No definite answer; NOT sufficient.

Combining (1) and (2), again we take the same examples, so there is no additional info; NOT sufficient.

The correct answer is E.
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