@karen9526 quantifier statements do not have contrapositives like Sufficient & Necessary statements.
They can be reversed with the only caveat being that "most" becomes "some" when you reverse it.
For a far more in-depth discussion of these concepts, please check out our video lesson for Quantifiers.
Hope this helps! Please let us know if you have any other questions.
karen9526June 6, 2016
Ohhh okay! Got it, thanks!
arctan1September 25, 2018
I don't understand, why the contra positive of [not Z-some-A] is [not A-some-not Z] and not [A-some-not Z]? What I thought the logic chain would look like is [not Z - > C-some-A], which might be wrong because the sufficient and necessary premises are switched, but that still doesn't explain why the contra positive of [not Z-some-A] is [not A-some-not Z].
rcantoral95June 28, 2019
Hello, as you mention above, quantifier statements do not have contrapositives. Why then does [not z-some-A] become [not A-some-not Z]? A pure reversal of the conclusion provided would be [A-some-not Z], no? Thanks for any clarification.
RaviJune 28, 2019
@karen9526,
Happy we could help! Let us know if you have any other questions!
@arctan1 and @noname,
Happy to help.
You are correct; there is a typo in the answer explanation, and I've alerted the technical team about it and have asked them to fix it.
The contrapositive of not Z - some - A is A - some - not Z as you correctly pointed out. Sorry for any confusion this caused you.
