Mind challange when friends buys a car

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Four friends, A, B, C, and D, are attempting to determine the order of their first four trips in a way that satisfies specific conditions. The conditions dictate that if D goes first, C must go third, and if A or D takes the second trip, C must take the first. Additionally, if A gets the third trip, B wants the second, and if D is last, C must be third and A first. Participants in the discussion explore various trip orders, with some suggesting combinations like ACDB and BCDA, but these are found to violate the established conditions. The consensus emerges that the only order satisfying all conditions is ABCD. The discussion emphasizes the importance of carefully analyzing the implications of each condition to arrive at a valid solution. Overall, the conversation highlights the complexity of the problem and the need for thorough justification of proposed solutions.
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Four friends A, B, C and D are buying a car together.
They agree that everyone should have one of the first four trips all alone.

But the following conditions apply:

1. If D is allowed to get on the first trip, C would have the third trip.

2. If A or D take the second trip, C would have the first trip.

3. If and only if A receives the third trip, B want to have the second trip.

4. Will D get the third trip, A wants the second trip.

5. Will D get the last trip would C have the third and A the first.

In what possible orders can they take the first four trips so that all is happy?
Motivate your answer.

Good luck,folks! =)
 
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Welcome to PF, Grinder! :smile:

CABD, CDAB, or CDBA
 
:smile: Thanks!

You have to justify the thought. Are there more? ;)

/Grinder
 
I like Serena said:
CABD, CDAB, or CDBA
Unless I am misunderstanding the conditions, your first answer violates condition 5, and your second answer violates condition 3. Only your third answer satisfies all 5 conditions. Additionally there is
CADB

Justification is an exhaustive search of all possibilities :smile:
 
DaleSpam said:
Unless I am misunderstanding the conditions, your first answer violates condition 5, and your second answer violates condition 3. Only your third answer satisfies all 5 conditions. Additionally there is
CADB

Justification is an exhaustive search of all possibilities :smile:

Oops! I mistyped my first solution and miss checked my second solution. :redface:
Grinder said:
:smile: Thanks!

You have to justify the thought. Are there more? ;)

/Grinder

No, there are no more:

It is easiest to verify the possibilities for D.
If D is first, the rules dictate uniquely when the others go, leading to a contradiction.
With D second, the order has to be CDBA.
With D third, CADB follows.
Finally with D 4th, we get another contradiction.
 
Hi!

What about ACDB and BCDA then? :wink:

What conditions are they violate? Or do they satisfy all conditions?? :smile:

/Grinder:biggrin:


and yes...I found the smilie button!
 
Grinder said:
Hi!

What about ACDB and BCDA then? :wink:

What conditions are they violate? Or do they satisfy all conditions?? :smile:

/Grinder:biggrin:


and yes...I found the smilie button!

"4. Will D get the third trip, A wants the second trip."
 
every one is wrong here... i will tell you how...
 
go back read the question again and solve it...
 
  • #10
ACDB and BCDA is wrong
 
  • #11
It is easiest to verify the possibilities for D. but If D is first, the rules dictate uniquely when the others go, leading to a wrong answer.With D the order D has to be CDBA.With D third, CADB follows.Finally with D fourth, we get another wrong answer.
 
  • #12
Hi everyone,

Unless I am misreading the question, the answer is ABCD. To me the list of conditions is just that a list. IF this one does this than that one will be satisfied if he does this. In that case the only condition that has everyone happy in the end is condition 5 If D is last then C wants to be third and A wants to be first. That leaves B to be second.

Did I misread the question?
 
  • #13
Unless I am mis-reading this, the answer is CADB
 
  • #14
This one wasn't too hard. I came up with the following answer, if there's any flaws I'd like them to be pointed out.
CDBA
 
  • #15
CADB @@v hehe.. If I understood it correctly?
 
  • #16
I don't think that I understand this correctly
 
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