SA drills? Help with old (basically ancient) PT's

TheAnxious0L

Hey guys,

i'm using the cambridge drills to practice SA questions, I'm wondering if someone has access to them and could help me out? It's question 15 and question 16. They are from prep test 2 S2 Q17, and PT 3 S2 Q12.

Cannot for the life of me understand what I did wrong. Not sure what the rules are with writing out problems that aren't posted in 7sage, but if someone has these drills, could you DM me? (or post the explanation here, if that's allowed)?

Thanks!

LSATcantwin

Question 2.2.17 is a Must Be False question not a SA.

Question 3.2.12

Lets take a look at it.

The first thing I do with a SA, and really any questions, is identify the conclusion.
here the conclusion is;

Con; Thus, photovoltic power plants (PPP) offer a less expensive approach to meeting demand for electricity than do traditional power plants(TPP).

The next thing I do is identify the support;

P1; As a result of technological advances, the cost of producing electric power at PPP is 1/10th what it was 20 years ago.

P2; Corresponding costs for TPP has increased.

Lets think about this for a second. What do we need to know in order to make this conclusion valid? Well, we need to make it so that the cost of PPP power is less than TPP power. As of right now we don't know that PPP is cheaper than TPP. We only know that PPP got cheaper and TPP got more expensive.

Answer Choice D;

Twenty years ago, the cost of producing electric power at a PPP was less than 10 times the cost of producing power at TPP.

this gives us that base line now. Now we know that PPP was less than 10 times the cost of TPP.

It's math at this point.

If 20 years ago TPP was $10, and PPP was less than 10 times that, PPP would have to be $99 or less.

Now because of technology PPP is 1/10th the cost it use to be which is $9.9. AND we know that TPP has increased a bit.

TPP now $11
PPP now $9.9

This makes it true.

Now that all seems long and convoluted. So you need to see that what AC D does is it fills in a gap.

We know that PPP is cheaper now and TPP is more expensive. What we don't have is a way to compare them because we don't know what each cost. Answer Choice D provides us with that mechanism.

Hope this helps and doesn't confuse you.