last question for today

Tinkle45

last question for today
« on: July 20, 2007, 05:28:39 PM »
Premise: Some Xs are Ys
Premise: All Ys are Z's
Premise:
Conclusion: SOme Ws and Z's

this is how i drew

W--> XsomeY-->Z

is this correct
The missing premise is All W's are X?
because the right answer is all Xs are Ws?

Tinkle45

Re: last question for today
« Reply #1 on: July 21, 2007, 08:29:39 AM »
Premise: Some Xs are Ys
Premise: All Ys are Z's
Premise:
Conclusion: SOme Ws and Z's

this is how i drew

W--> XsomeY-->Z

is this correct
The missing premise is All W's are X?
because the right answer is all Xs are Ws?

You have it reversed in part of your text. Adding in X --> W would lock it up.

--> W
/
X Y --> Z

Valid conclusion:  W   Z

thankkkk you Jeffort! makes so much sense.

but please tell me i am reasoning right in this one:

No A's are B's . Some Bs are C.

A<--|--> Bsome C
does not it give me: Asomenot C?
I don't know... this problem came to me in my dream  ...shows how obsessed i am with LSAT

peach

Re: last question for today
« Reply #2 on: July 21, 2007, 09:32:17 AM »
I believe you have this reversed. You should arrive at:
C some not A. Remember, the A term is the one that is attached to "not" since it is the one that cannot go with B.

Tinkle45

Re: last question for today
« Reply #3 on: July 22, 2007, 03:38:23 PM »
Jeffort you are a gem!!!!!!!!