# To be considered for this year's Gillespie Grant, applications must be received in Gillespie City by October. It can ...

JLA on June 3, 2019

Explanation

I'm unsure as to why the correct answer in this case is actually the correct answer. In the video lessons I learned that "only if" is equivalent to "if and only if." So, when saying that her application would be reviewed "only if" it was mailed 10 days before excludes all other considerations for it being reviewed. Any help would be appreciated, thanks!

Replies

Ravi on June 4, 2019

@JLA,

In the video lessons, "only if" and "if and only if" are not described
as equivalent statements.

"Only if" introduces the necessary condition, whereas "if and only if
is a bi-conditional statement."

I will go to Mars only if I have a rocket

Mars - >rocket

I will go to the movie if and only if David comes with me

Movie< - >David comes

Considered for Grant - >Application Received by Oct. 1

Sometimes it takes mail 10 days to get from Greendale to Gillespie

Conclusion: Send application by regular mail - >must mail 10 days
before the due date

The conclusion is incorrect in saying that the mail has to be sent 10
days before the due date. All that we know is that it may take up to
10 days for the mail to get from Greendale to Gillespie, but that
doesn't mean that the mail always takes 10 days. It's possible some
mail arrives well before 10 days.

(C) says, "does not consider the minimum amount of time it takes
regular mail from Greendale to reach Gillespie City"

(C) is precisely what we had anticipated in our analysis. The argument
is not thinking about the possibility that it may sometimes take fewer
than 10 days for mail to go from Greendale to Gillespie. In those
instances, it wouldn't be necessary to mail in an application 10 days
before it's due. Thus, (C) is the correct answer.

Hope this helps. Let us know if you have any more questions!

ScarlettY on June 6, 2023

Hello. I understood the part “it may sometimes take fewer than 10 days before it’s due.” But since, there is the possibility that it may takes 10 days, isn’t it to be safe to send it 10 days before due dates? Because you never know how long it will takes for mail to be delivered.

Emil-Kunkin on June 7, 2023

You're correct that she probably should send it in 10 days before, but the argument goes too far. It says that the only way she will be considered is if she sends it in 10 days early. She could in reality still be considered if it gets there after 3 days and she sent it in 5, but the argument goes too far in assuming this is impossible.