Question on Linear Set Up Practice Drill

[brown117]

in the Linear Practice Set Up Drill question 12 in book one on page3-37 .My question is for diagramming rule number six.

Applying the two step Unless Equation Process I diagrammed it as follows:

1) I made L the necessary condition and on Monday as it is being modified by unless
2) I negated is not Thursday and made it is Thursday and the sufficient condition.

if R Thursday L Monday

I also diagrammed the contrapositive

L Not Monday then R is not Thursday.

However when I read the answer it stated that answer choice A was incorrect because it reversed the last rule and is therefore Not Necessarily True. I understand the right answer however I want to know if I diagrammed it incorrectly according to the book and if so what is the proper diagramming of rule number six.

[Steve Stein]

Hi,

Thanks for your question. You got the diagram right--consistent with the diagram in the explanation:
Diagram 1: R on Thursday L on Monday

Diagram 2: Contrapositive: L NOT on Monday R NOT on Thursday.

Answer choice A claims that When L is on Monday, R is on Thursday:

L on Monday R on Thursday

This is a mistaken reversal of the Diagram 1 above. While we know that:
R on Thursday dictates L on Monday,

...it is not necessarily true that L on Monday dictates R on Thursday.

I hope that's helpful--please let me know whether this clears that one up--thanks!

~Steve