Okay
I understand and see why A is correct.
But, when I was going through answer choice (A) I saw the "no" in the first half of the conditional and used that to negate necessary.
After doing that I get SL --> IMP
But
If it is diagrammed as written it's /SL --> /IMP, we get the right answer.
Looking for a little help as to why using the negate necessary rule with "no" didnt give me the right statement.
PT30 Sec2 Question 18 Forum
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LauraS
- Posts: 29
- Joined: Tue Feb 25, 2014 4:48 am
Re: PT30 Sec2 Question 18
Hi, Bilka --
I'm not sure what you're referring to when you say "negate necessary, " but my guess is that you want to take the contrapositive, which is the logical equivalent of the statement.
To take the contrapositive, you need to do two things:
a) switch what's on the right and left of the arrow and
b) negate both sides.
One way of understanding it is that if the necessary condition (right side) isn't true, then the sufficient condition (left side) can't be true.
So:
no SL -> no IMP
is equivalent to
IMP -> SL
It looks like you negated both sides but didn't switch them.
Let's walk through the whole question, just to make sure everything's clear.
The stimulus says:
a) IMP -> GS
the contrapositive of that is:
no GS -> no IMP
b) no SL -> no GS
c) a statement about understanding one's musical roots that's irrelevant for our purposes.
Answer choice a) says:
no SL -> no IMP
Can we combine the statements in the stimulus so that they say no SL -> no IMP, making answer a) correct? Yes.
no SL -> no GS
no GS -> no IMP
therefore: no SL -> no IMP
Does this answer your question? If not, please ask further questions!
I'm not sure what you're referring to when you say "negate necessary, " but my guess is that you want to take the contrapositive, which is the logical equivalent of the statement.
To take the contrapositive, you need to do two things:
a) switch what's on the right and left of the arrow and
b) negate both sides.
One way of understanding it is that if the necessary condition (right side) isn't true, then the sufficient condition (left side) can't be true.
So:
no SL -> no IMP
is equivalent to
IMP -> SL
It looks like you negated both sides but didn't switch them.
Let's walk through the whole question, just to make sure everything's clear.
The stimulus says:
a) IMP -> GS
the contrapositive of that is:
no GS -> no IMP
b) no SL -> no GS
c) a statement about understanding one's musical roots that's irrelevant for our purposes.
Answer choice a) says:
no SL -> no IMP
Can we combine the statements in the stimulus so that they say no SL -> no IMP, making answer a) correct? Yes.
no SL -> no GS
no GS -> no IMP
therefore: no SL -> no IMP
Does this answer your question? If not, please ask further questions!
