Manager

David makes two conflicting statements "Carol is the manager." and "Alice is the manager." He must be the only liar -- the manager .

Carol and Alice both say that David is the manager. At least one of them speaks the truth. Thus, David is the manager.

Carol: "David is the manager."

David: "Carol is the manager."

this two statements are conflicting.so,one of them is the liar manager.and so,other statements are true.

as,Alice declares $\boxed{David}$ as the manager-so David must be the manager.......[according to the condition.]

Let's assume Alice is the manager. Then her statement "Bob is an engineer" is a lie, so Bob is the manager. This is a contradiction, so Alice must be an engineer.

Whatever Alice says is true, so "David is the manager".

1- David states that Carol is the manager AND Alice is the manager, which is impossible, and... 2- Carol and Alice together say that David is that manager. There's only 1 manager. One of them would have to be telling the truth. So if they both agree, then either of them aren't the manager, AND they're proving that David is the manager by truthfully agreeing with each other by being one of the 3 engineers.

In 2nd conversation, Carol and David tell each other manager. So one of them must be manager and he/she is telling lie.

So, we are now sure that Alice and Bob are engineer and they tell truth.

In 3rd conversation, Alice said, "David is the manager". We sure before that Alice tells truth. So it's a true statement.

Now we can surely say that 'David' is the manager.

Quite simple. David makes 2 contradicting statements, therefore he is lying and is the manager.

Because he gives two different opinions in manager

Alice and collar say that David is manager and if two are saying than one must tell the truth.

Alice and Bob say that they both are engineers making it plausible since only 1 would lie and the 3 would speak the truth knowing this Alice says David is the manager, making David the manager since Alice is a engineer

David contradicts himself. Clearly a manager type.

Carol and David say that they are the managers. Since there is only one manager; one of them must be lying. Next, David says that Alice and Carol are both managers; so David must be the liar. Therefore, David is the manager.

If David is the manger then Alice isn't meaning she is telling the truth and David is the manager. A feedback loop

David is the lier

David makes two conflicting statements "Carol is the manager." and "Alice is the manager." He must be the only liar -- the manager

Firstly, David contradicts himself so he must be lying. Secondly, Alice and Bob have to be engineers because if one is lying then they would both be managers which is againast the rules. Since we know Alice tells the truth, we can believe her when she says David is the manager.

Bob and Alice both say each other is an engineer. Since they can't both be managers, one of them must be telling the truth. Therefore one confirms the other as a truth teller, making the other one the same as well. David says Alice is the manager, we know this to not be true, therefore David is the manager.

Its david

David says two conflicting statements "Carol is the manager" and "Alice is the manager". Thus David is the manger(liar).

Two people both claim David is the manager. At least one is telling the truth.

Two people confirmed the same story that David is the manager. Bob and Alice already confirmed that they were engineers assuming that they are both telling the truth you can assume either Carol or David is the manager. David said that Carol is the manager and Carol confirms David is the magaer, however Alice and Carol both confirm that David is the manager. Since Alice was confirmed as an engineer by Bob you can conclude that David is the manager

David says that both Carol and Alice are Managers so he must be lying about a least one of them. We then see both Carol and Alice say that David is the Manager, so David is the manager.

If we find two of the same statements then that means that 1/2 is a lier and then the other must be a truth. Therefore from that, we can work out everyone else that lies and tells the truth and from that tell who is a manager and who is an engineer.

Ask everyone to point to the manager. The majority will point at the lieing manager. Lol

David is the manager because he is only one who is telling lie

David. He's the only one not wearing a T-shirt!

Does it bother anyone else that the Manager is the liar?

There is only 1 liar. David disagrees with 2 people. David, you liar!

2 people says David is manager.And in question it mentions that only manager lies.And there is only 1 manager.

Alice and Bob both say each of them are engineers. If one is lying, they are the manager. But if they're lying, the other is lying, and is also, therefore the manager. So we know they are both engineers. Then Carol says that David is the manager, and David says that Carol is the manager. One of them is lying, and therefore the manager. Alice agrees that David is the manager. We know Alice is an engineer, and therefore is telling the truth. Also, there is only one manager. In order for Alice or Carol to be lying, the other is also lying. Therefore, they both must be telling the truth. After that we have further proof because David contradicts his earlier statement and says Alice is the manager so we know both of those statements are a lie. Also, the statement contradicts the statement Bob made. We know Bob tells the truth, so we know David's Statement is a lie.

David was the liar as his two statements didn't go together-Alice is the manager, and Carol is the manager. Also, two (and one of them must be an engineer, telling the truth) people said David was the manager. Therefore, David, the liar, is the manager.

Carol and David contradict each other, so one of them is the manager.

Alice and David also contradict each other, so one of them is the manager.

David is the only person belonging to both pairs, thus he is the manager.

Either Carol or David is the liar considering that there is only one manager (the manager can't be Carol and David at the same time). There is only one liar among the four. So both Alice and Bob must be truth tellers. According to Alice, David is indeed the manager.

Since "David is the manager" is said by both Alice and Carol, this statement must be true; otherwise there would be two liars and hence two managers. Therefore, David is the manager.

If there is only one manager then Bob and Alice can not be telling lies that means Alice's statements are true and that tells us that David is the manager

Alice and Bob both says that the other one is an engineer. If one if them lies, that means that he is the manager, but also means that the other one as well which is impossible, so both are saying the truth.

Alice also says that David is the manager, and since she is saying the truth, it means that he is really the manger.

Hence, the answer is David.

The first thing I saw is that Carol and David contradict each other, so one of them must be lying. To find out which, we listen to Alice, who we now know is telling the truth.

David have given two contradictory statements - (1- carol => manager - 2- alice => manager) - Conclusion : david => liar and we know that liar => manager - so david => manager

Two people said that David was the manager so one them could have been lying but one one person lies so they both couldn't be wrong that's a 50/50 chance. Also David said that Alice and Carol was manager and two people can't be the manager at once so he was lying.

David has stated that both Carol and Alice is the manager, since David states two different people as the manager and the limitation of only having one manager, David has lied. Engineers can only tell the truth, this makes David the manager.

David says that Carol is the manager, and that Alice is the manager. However, there can only be one manager, so David must have lied at least one of the times he spoke. So he cannot be an engineer, so David must be the manager.