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Author Topic: Conditional Statements --Help me out!  (Read 484 times)

Xlogic

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Conditional Statements --Help me out!
« on: July 26, 2011, 06:27:32 PM »
I've worked on LR and LG questions that use "OR" in creative ways. Sometimes I get tricked, especially when I expect one conditional form, but the LSAT is looking for another.

Here are a few of them...

Mary will go to the Shop or watch a movie
Mary will either go to the shop or watch a movie
Mary will either go to the shop else she will watch a movie
Mary will go to the shop but she will not watch a movie
Mary will go to the shop and she will watch a movie

If Mary will watch a movie, she will not go to the shop
If Mary does not watch a movie, she will go to the shop

Could you help translate these sentences into "or", "and" or conditional statements
> M = Mary, S = Shop, W = Watch movie

Thanks!

BraveDave

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Re: Conditional Statements --Help me out!
« Reply #1 on: July 27, 2011, 12:55:30 AM »

Mary will go to the Shop or watch a movie --- M ->S or W;
Mary will either go to the shop or watch a movie --- M->S or W
Mary will either go to the shop else she will watch a movie --- if Sm(mary shops) -> no Wm (Mary movie), if Mm -> no Sm
Mary will go to the shop but she will not watch a movie --- Sm; no Wm
Mary will go to the shop and she will watch a movie --- Sm and Wm

If Mary will watch a movie, she will not go to the shop --- if Wm -> no Sm; if Sm -> no Wm
If Mary does not watch a movie, she will go to the shop --- if no Wm -> Sm; if no Sm -> Wm

Could you help translate these sentences into "or", "and" or conditional statements
> M = Mary, S = Shop, W = Watch movie

Thanks!


Not sure about the third one but others should be correct:)

Xlogic

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Re: Conditional Statements --Help me out!
« Reply #2 on: July 27, 2011, 03:19:30 AM »
@BraveDave, My logic statements are very similar to yours. Thanks.
Note: Bolded extra inferences.

MW = Mary watch a movie
MS = Mary go to the shop


Mary will go to the Shop or watch a movie
> (Inclusive OR) MS or MW or (MS and MW)

Mary will either go to the shop or watch a movie
> (Inclusive OR) MS or MW or (MS and MW)

Mary will either go to the shop else she will watch a movie
> (Exclusive OR) MS or MW
> Inference: MS --> not MW, 
> Inference: MW --> not MS (contrapositive)


Mary will go to the shop but she will not watch a movie
> MS and not MW

Mary will go to the shop and she will watch a movie
> MS and MW

If Mary will watch a movie, she will not go to the shop
> MW --> not MS
> MS --> not MW (contrapositive)

If Mary does not watch a movie, she will go to the shop
> not MW --> MS
> not MS --> MW (contrapositive)