Is this wrong because there are other factors leading to the conclusion that Sally did well on the LSAT that are not discussed?

No.

You can't conclude anything because the only info given is:

P 1: Well → Mastered

P 2: Mastered


This question is designed to show you that you can't take the info above and conclude that "Sally did well on the LSAT." In other words, the question is designed to show you how the Converse Error works.

The Converse Error comes up a lot on the LSAT, so it's important that you learn how to spot it, and how to avoid committing it.


Note that IF you had:

P 1: Mastered → Well

P 2: Mastered

then you could conclude that "Sally did well on the LSAT."

What is converse error?

Converse error is like what's discussed in the problem. Just because someone masters a portion of the LSAT doesn't mean she does well in the test. Here's another example: Every great city has a college. City X has 10. Therefore City X is a great city? We can't really say. It may or it may not be. What if the crime rate is high? What if the pollution rate is high?

What Is the best way to avoiding making the converse error mistake ?

Recognize if the reciprocal of an if-then statement is true. In this example, the properties are associative not commutative.
ie. basketball players are tall-John is tall-John is a basketball player.
Theyre logic questions for a reason, follow them to LOGICAL co conclusion

It appeared to me that 'in order to' in the first statement actually inverted the relationship. That is to say, 'if you master conditionals then you will do well on the LSAT.' The mastering of conditionals is implied as the antecedent and therefore you can conclude that she did well on the LSAT. What did I miss?

When looking at a converse or sometimes called the reciprocity trap, it's easy to look at them as equations instead of if-then statements.
E.g. If I study property law -> you study property law. This does not mean:

If you study property law -> I study property law

It DOES mean:

If I DON'T study property law-> you don't study property law.

IPL->YPL to test this FLIP and NEGATE
~YPL->~IPL

I'll see if I can use math to explain. This converse error is a matter of necessity. Look at this true statement, 1+1=2. You know in your head that 2=1+1, BUT is that the ONLY way you can get 2 for an answer? NO!
Converse errors are the most common pitfall on the LSAT. When a CONDITION is given, the converse is not necessarily true but, the CONTRAPOSITIVE is ALWAYS TRUE. :)

Clayton, right on.