Government statistics show that the real (adjusted for inflation) average income for families has risen over the last...

Ravi on July 23, 2019

@SamBaucom,

Happy to help. Let's take a look at (A) and (D).

This is a tricky question, so let's delve into the details. The flaw
in the stimulus is that the argument is assuming that the Andersen
family must have made a lower amount in the previous 5 years than they
did this year. However, must this be true? Not at all. They're just
one family, and we can't make any sort of conclusion about the change
in income levels for a single family based on the average of all
families.

Let's pretend that 5 years ago, the average family income was
$100,000, and now it's $200,000. Let's accept that the Andersen family
is making $200,000 this year. It's entirely possible that they were
making way more in the previous five years (let's say $500,000). We
don't have enough information about their past income history, and the
argument is assuming that they earned less in the previous five years,
which is where the flaw in the argument is.

(A) says, "ambiguously uses the term "average" in two different senses"

The term "average" is being used in the same way in the stimulus. In
both cases, it refers to the average family income. Thus, we can get
rid of (A).

(D) says, "fails to consider the possibility that the Andersen
family's real income was above average in the recent past"

(D) does a great job in summarizing the flaw of the argument. (D) is
saying that it is possible that in the last 5 years, the Andersen
family's income was greater than the current average family income.
This is what the author is overlooking, as we don't have any
information about any single family's change in income based solely on
an average. Thus, it's possible that the Andersen family might not
have had an increase in income over the previous 5 years, so (D) is
the correct answer choice.

Does this make sense? Let us know if you have any other questions!

SamBaucom on July 23, 2019

Yes that makes perfect sense! Thanks so much

Ravi on August 5, 2019

@SamBaucom, you're welcome! Let us know if you have any other questions!

saskipper on June 20, 2020

Thank you for this explanation, it was very helpful!