starryskyes wrote:

Hi guys,

I have a question to the fundamentals of DS questions.

I know that both DS statements are true and non-contradictory. Thus, I was quite baffled to do a DS question where statement one gives me two quadratic roots: -23, 23, but statement two gives me the quadratic roots: -23, -17.

Could someone explain how this is possible? In my mind, the statements are contradictory then, since only one root is common between the two statements.

The question was from

Veritas Prep CAT#2 with Question ID: 07578 (not sure if I'm allowed to post the question here due to copyright).

Thanks!

You are right - both DS statements are true and non-contradictory. The point is that in this question too, the two statements are true and non contradictory. Let me explain.

Let's simplify:

Question stem: What is x?

Stmnt 1: x is either 23 or -23.

Stmnt 2: x is either -23 or -17.

Now you know that both statements are true. So the value of x has to be one of 23 and -23. It also has to be one of -23 and -17. So the only value that x can take is -23. That will keep both statements true.

In that case, x will be one of 23 and -23 (it is -23) and x will also be one of -23 and -17 (it is -23).

The statements are not contradictory. Using both, we realise that the only value x can take is -23.

I hope this sorts out your doubt!

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Karishma

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