Aquamarine
Thanks Received: 0
Forum Guests
 
Posts: 43
Joined: August 21st, 2013
 
 
 

Cracking Substitution Qs

by Aquamarine Wed Aug 17, 2016 1:29 am

I'm having hard time to solve substitution Qs like PT58,S2,Q12 and PT59,S1,Q10.
Is there any effective strategies to crack this kind of the Qs?

Please someone enlighten me.
Thanks in advance!
User avatar
 
ohthatpatrick
Thanks Received: 3805
Atticus Finch
Atticus Finch
 
Posts: 4661
Joined: April 01st, 2011
 
 
 

Re: Cracking Substitution Qs

by ohthatpatrick Wed Aug 24, 2016 6:31 pm

It looks like you're a public user, so you not might be able to access this link, but here's a chapter devoted to that.

Link to bonus chapter (scroll down until you see Rule Equivalency)
http://www.manhattanlsat.com/training-center.cfm

In short, I made two passes on the answer choices (you can literally take Filter #1 through all five answers and THEN take Filter #2 through all five ... or you could just apply Filter #2 on any answer choice that initially makes it past Filter #1).

Filter #1 - Answer is wrong because it's TOO RESTRICTIVE
Use previous work to eliminate these answers.

If any rule is telling you that something you COULD do before is NO LONGER possible, then it's wrong. For each answer choice you read, scan previous work for counterexamples. If you have a counterexample, then eliminate that choice. If you don't have a counterexample, at least ask yourself, "DID this have to be true before?"

Filter #2 - Answer is wrong because it's TOO PERMISSIVE
Make sure the answer choice does the work of the Old Rule

For each answer choice, ask yourself if you could BREAK the Old Rule while FOLLOWING the New Rule.

There are a lot of answer choices that pass filter 1 by describing a previous implication of the game. For example, say that you're replacing a rule that "H is before K and P". This might have started off a whole Relative Ordering tree.

An answer choice might accurately say that "H can only be 1 or 2". That would probably get through Filter 1. It WAS true that H was always one of the first 2. But does that do the work of forcing H before K and P?

Not on its own. If H is 2, then K or P could still be at 1. You could BREAK the old rule while FOLLOWING the new rule.

If an answer choice passes both tests, it's correct!