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HOW DO WE SOLVE SUCH REASONING QUESTIONS?...PLZ HELP TG
by jaydeep chakraborty - Monday, 7 September 2009, 09:16 PM
 

PLEASE TELL HOW THESE QUESTIONS CAN BE SOLVED BY BREAKING THE SENTENCE INTO PARTS,NAMING THEM AS p,q,r,s etc. AND THEN APPLYING BOOLEAN ALGEBRA.

I SAW SOME OF THE SOLUTION BUT COULD NOT GET THE APPROACH,SO PLZ EXPLAIN IN DETAIL.....THANKS IN ADVANC.

 

CHOOSE THE RIGHT ALTERNATIVE WHICH CAN BE LOGICALLY CONCLUDED:-

1.The speaker will adjourn the house, if the leaders create havoc and do not comply.

A. The speaker adjourned the house, as the leaders were creating havoc and were not complying

B. The leaders did not create havoc and did not comply means the speaker will adjourn the house.      

C. The leaders did not create havoc and complied, hence the speaker did not adjourn the house.

D. The speaker did not adjourn the house but the leaders were creating havoc implies that the leaders complied.

 

2.All cats are dogs is true and no dog is rat is false, only if no cat is rat is false or some rats are not dogs is true.

A.No cat is rat is false, some rats are not dogs is false and no dog is rat is false, hence all cats are dogs is false.

B.No cat is rat is true, means that no dog is rat is true or all cats are dogs is false. 

C.Some rats are not dogs is false, no cat is rat is true and all cats are dogs is true, hence no dog is rat is true.

D.More than one of the above

Re: HOW DO WE SOLVE SUCH REASONING QUESTIONS?...PLZ HELP TG
by deepak nayak - Thursday, 10 September 2009, 05:46 PM
  1.The speaker will adjourn the house, if the leaders create havoc and do not comply.

                         B                                 if                           A                                             

The given statement is of type : B happens when A happens
so, whenever A happens, B will happen, but B can also happen for some other reason.
But, if B didn't happen we can conclude that A didn't happen.
Mathematically, it is written as           A => B
                                                    then, B' => A'

Here, the condition statement A is also a combination of conditions:

lets. say leaders create havoc -- a

             donot comply -- b
so, A = a AND b

Now coming to the option

A) a And b i.e A is true, so B will be true, that's what the first part says B happened. This is just the restatement of the question statement itself.so, it can't be the conclusion.
B) a' and b, this is neither A nor A', so nothing can be said
C) a' and b', see this is not A', because A' = (a' OR b') nothing can be said
D) first part is B', so it implies A' i.e A didn't happened. but A' = a' OR b'. (if  x OR y is true, and x is false then we can conclude that y is true, but if x is true, we can't say y may or may not be true). here given is a i.e NOT a' so b' has to be true, ant that's what last part says.
so, the correct ans is (D).


2.All cats are dogs is true and no dog is rat is false, only if no cat is rat is false or some rats are not dogs is true.

This is somewhat different from previous,
All cats are dogs is true and no dog is rat is false = B
no cat is rat is false or some rats are not dogs is true. = A
here, it says B only when A. i.e there is no other reason of B to happen.
We represent it as A <=> B. i.e if A happens, B will happen and also if B happened, then A must have happened, because there is only one reason for B to happen and i.e A. so A' => B' because if A will not happen then B will also not happen.

lets, break the statement into parts:
All cats are dogs = a
no dog is rat = b
no cat is rat=c

some rats are not dogs=d
so our A = a AND b'
and B = c' OR d
Now, lets see the options:

A) c'AND d' AND b' means a'. here c' AND d' not logically related to either B or B', so no conclusion
B)c means b OR a'. See, A=a AND b', hence A' = a' OR b, but B'=c AND d', so first part is neither B nor B'.
C)d' AND c i.e B'. from B' we can conclude A' ie. a' OR b. and given is a i.e a' false so b has to be true and that's the last part. so, this is the correct ans.




Re: HOW DO WE SOLVE SUCH REASONING QUESTIONS?...PLZ HELP TG
by Kunal Gupta - Friday, 11 September 2009, 12:09 AM
 

Doesnt option 1 looks like answer for one..

Option A conveys the same thing as original

Re: HOW DO WE SOLVE SUCH REASONING QUESTIONS?...PLZ HELP TG
by Kunal Gupta - Sunday, 13 September 2009, 12:59 PM
 

dagny,

pls help

Re: HOW DO WE SOLVE SUCH REASONING QUESTIONS?...PLZ HELP TG
by sushmitaTG TEAM - Friday, 8 November 2013, 03:49 PM
  Hi,
For the approach to these type of questions, kindly refer to the article in this link:
http://totalgadha.com/mod/forum/discuss.php?d=8431
 It will clear all you doubts. smile