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Off-Topic Discussion => General Discussion => Topic started by: blackhole on November 01, 2008, 12:27:41 am

Title: SAT Math 2 Practice
Post by: blackhole on November 01, 2008, 12:27:41 am: Quote
"If all Poggles are Quibbles, then Rizzles exist." Assuming that the above statement is true, which of the following statements must also be true?
   a. If Rizzles exist, then all Poggles are Quibbles.
   b. If Rizzles do not exist, then no Poggles are Quibbles.
   c. If some Poggles are not Quibbles, then Rizzles do not exist.
   d. If Rizzles do not exist, then at least one Poggle is not a Quibble.
   e. If all Quibbles are Poggles, then Rizzles exist.

:wtf:

(the correct answer is d)
Title: Re: SAT Math 2 Practice
Post by: redsniper on November 01, 2008, 01:42:37 am: I don't see why it can't be c.
Title: Re: SAT Math 2 Practice
Post by: Maniax on November 01, 2008, 01:50:09 am: Because there's no part of the statement that says the only way riggles exist is if all poggles are quibbles.
Title: Re: SAT Math 2 Practice
Post by: Colonol Dekker on November 01, 2008, 01:51:50 am: I don't see why it can't be B either. And isn't this question focused on comprehension. I don't see a math element to it.
Title: Re: SAT Math 2 Practice
Post by: Hellstryker on November 01, 2008, 01:52:18 am: Quote from: redsniper on November 01, 2008, 01:42:37 am
I don't see why it can't be c.
Title: Re: SAT Math 2 Practice
Post by: Spicious on November 01, 2008, 01:55:02 am: It's pretty straightforward using first order logic.
(For all x Poggle(x) => Qubble(x)) => there exists y such that Rizzle(y).
The only statement that can be proven from that is D.

C isn't true since implication operates one way.
B isn't true since the negation of all is merely that there exists one that isn't (in this case D).
Title: Re: SAT Math 2 Practice
Post by: Colonol Dekker on November 01, 2008, 02:01:40 am: Yeah i follow now. I read the options slower. My brain hurts i'm getting on a train now and sleeping.
Title: Re: SAT Math 2 Practice
Post by: Topgun on November 01, 2008, 10:10:03 am: I think they should change the "if" to "If and only if".
Title: Re: SAT Math 2 Practice
Post by: Rian on November 01, 2008, 11:45:36 am: But wouldn’t that change the answer?
Title: Re: SAT Math 2 Practice
Post by: Dark RevenantX on November 01, 2008, 11:49:16 am: ****, I'm going to have to take the math2 subject test this year. I hope I don't get this (easy to solve) bull****, because I don't want two years of calculus to go wasted.
Title: Re: SAT Math 2 Practice
Post by: CP5670 on November 01, 2008, 01:36:48 pm: That test doesn't cover anything beyond basic trignometry from what I remember.
Title: Re: SAT Math 2 Practice
Post by: BloodEagle on November 01, 2008, 01:49:16 pm: Quote from: Topgun on November 01, 2008, 10:10:03 am
I think they should change the "if" to "If and only if".
Agreed.

I've always hated how test questions, with regards to every subject, were never absolute. I also hated how they were never checked for incorrect spelling or grammar usage.

Note: I am speaking about college-grade tests, in case you were wondering.
Title: Re: SAT Math 2 Practice
Post by: Spicious on November 01, 2008, 03:06:14 pm: Quote from: BloodEagle on November 01, 2008, 01:49:16 pm
Quote from: Topgun on November 01, 2008, 10:10:03 am
I think they should change the "if" to "If and only if".
Agreed.

I've always hated how test questions, with regards to every subject, were never absolute. I also hated how they were never checked for incorrect spelling or grammar usage.

Note: I am speaking about college-grade tests, in case you were wondering.
Actually, this one is pretty absolute logically. Changing it to if and only if makes A and C valid answers.
Title: Re: SAT Math 2 Practice
Post by: blackhole on November 01, 2008, 06:46:22 pm: Thankfully, the actual SAT had none of this bullcrap on it.
Title: Re: SAT Math 2 Practice
Post by: Dark RevenantX on November 03, 2008, 07:14:56 pm: Yeah, the SAT had a different kind of bullcrap that was more annoying than retarded.
Title: Re: SAT Math 2 Practice
Post by: Topgun on November 03, 2008, 07:20:00 pm: When I took my SAT I bet I could have answered all the math questions correctly if I only had more time.