## Do grouping games other then in/out have contrapositives?

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itstime

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### Do grouping games other then in/out have contrapositives?

Meaning in an In/Out game

if a then not b
would contra into
if b then not a

but like in prep test 45 december of 2004 logic game #3 i do not know the proper way to diagram

I am not sure if when

Wendy appears in every photograph that selma appears in should look like

s --> w
and its contrapositive would then be
--w-- --> --s--

or is it s&w are in or neither s&w are in?

1) what would happen if we know W is in? W is the necessary and i always interpreted it as it would have to be the sufficient to know then necessary?

if it is s<-->w
then i would understand that if theres a w there must be a s
but when i do it individually getting a w would lead me to believe there could be a s or there could not be a s

2) what would happen if s is out based on this rule?

similarly when S appears in every photograph Y does not appear in

is it
--y-- --> s
and
--s-- --> y

or would the contra be instead
s --> --y--

-- letter -- means not

what inferences are made upon these rules?

Thanks