Whenever Joe's car is vacuumed, the employees of K & L Auto vacuum it; they are the only people who ever vacuum J...

Mehran on September 6, 2017

Hi @kyoon, thanks for your post.

Let's break down the stimulus first.

P: Whenever Joe's car is vacuumed, the employees of K&L Auto vacuum it; they are the only people who ever vacuum Joe's car.

JCV ==> K&LV

P: If the employees of K&L Auto vacuumed Joe's car, then Joe took his car to K&L Auto to be fixed.

K&LV ==> K&LF

P: Joe's car was recently vacuumed.

V (achieved)

C: Therefore, Joe took his car to K&L Auto to be fixed.

K&LF (achieved)

This is a sound logical argument following the transitive property, as follows:

JCV ==> K&LV ==> K&LF

We are told that JCV has happened (that is, Joe's car has been vacuumed).

We can then conclude that K&LF (that is, that Joe's car has been fixed at K&L)

Now let's consider answer choice (A):

P: Emily's water glass is wet.

W (achieved)

P: It would be wet only if she drank water from it this morning.

W ==> DW A.M.

P: Since the only time she drinks water in the morning is when she takes her medication,

DW A.M. ==> Medication

C: Emily took her medication this morning

Medication (achieved)

Again: this is a sound logical argument following the transitive property, as follows:

W ==> DW A.M. ==> Medication

Unlike the stimulus and the correct answer choice (A), answer choice (D) does not establish that a sufficient condition has been fulfilled. Rather, the conclusion itself is phrased in a conditional format ("Therefore, Linda runs out of coffee only on days that she is grumpy"). That is not parallel to the stimulus's reasoning.

Hope this helps! Please let us know if you have any additional questions.