AL, I don't think you understood this

Elena, that's not quite the meaning - the original post is an incomplete thought

Uly, it seems my translation is in line with yours but we don't say as you wrote it in Russian.

Разве нельзя подождать еще 10 минут? Почему бы не подождать еще 10 минут?

Elena, it seems to me that you're question merely asks if it's necessary to wait the 10 minutes. However, this post is about someone's reaction when they've already been told that they have to wait 10 minutes and they find that unreasonable. The speaker can't believe their reaction and is wondering WHY they find it so unreasonable: (to a stewardess) A: We landed 20 minutes ago - why can't we get off the plane? ST: There's a problem at the terminal. It'll be another 10 minutes. A: (to his wife) This is preposterous! How long are we supposed to sit in here?? Wife: What's so unreasonable about waiting 10 more minutes - we've already waited 20!!

In other words, this question means "what part of waiting 10 more minutes do you find so unreasonable?"

Uly, though I put a question mark, these phrases sound just as affirmative. They mean that it's not a problem if we wait for another 10 minutes. But after your explanation I'd write " Ничего страшного (ничего не случится)), если мы подождем еще 10 минут"

Yes, it's a rhetorical question about a reaction someone finds surprising.

I think my translation is correct.

But it doesn't even contain the word "unreasonable"

Uly, but you know that a word by word translation is not always good.
When we say Разве нельзя подождать еще 10 минут? it means we convince somebody to wait because it makes sense. It doesn't mean that somebody asks if it's necessary to wait another 10 minutes.
1. А: - Хватит, мне надоело ждать, я пошел.
Б: - Постой, не уходи, разве нельзя подождать еще 10 минут?

2. Стюардесса:- Высадка из самолета задерживается еще минут на 10.
Муж: - Это безобразие!
Жена: - Дорогой, ничего страшного, 20 минут прождали и 10 подождем.

I think it's impossible to include "unreasonable" in the Russian translation.

Или: "Разве так трудно подождать еще 10 минут"?

That's it! так трудно. The fact is that you need to use some kind of adjective because you're not referring to the waiting time per se, you're referring to the unreasonable reaction to the waiting time.

Elena, what Uly meant was that this phrase is a part of a conversation. Someone told someone that it was unreasonable to wait ten more minutes. And this phrase is a response to the previous statement. That's why it should contain "unreasonable" in the translation, because that's what they were talking about.

You examples show a totally different picture.

Great! Thanks! I agree it's better. But Разве нельзя подождать is almost the same)

Olga, I think we came to a consensus with Uly. Sometimes it doesn't make sense to make a word for word translation.

My examples express the same idea

I agree that word for word translations aren't good, but you left out the most important word :-)

But first I translated with "нельзя", it's almost the same :)

I don't know, when I saw this phrase I pictured something like this:
- We've been waiting for Mike for more than an hour now. He clearly is not coming. We have to go or we're going to miss the train.
- Let me call him one more time. Let's wait for another ten minutes and then we leave.
- Darling, there is no point in waiting any longer. He's not coming.
- What's so unreasonable about waiting ten more minutes?

In your example I'd translate it like "Может, все-таки подождем еще 10 минут?"

With this question you want to know why exactly the other person thinks that it's unreasonable to wait. You want to hear the reasons. Otherwise you could just say "Why not to wait ten more minutes?"

"Все-таки стоит подождать еще 10 минут" :)

I read the same situation into it as Olga. It's not a statement about the waiting, it's about what the LISTENER considers so unreasonable about the waiting that the speaker finds so curious.

Elena, when someone tells you that it's unreasonable to do something, do you always reply with "Может всё-таки стоит это сделать?"? :)

Olga, it depends). In any case we should find Russian equivalents for translations. In your example, may be "А почему ты не хочешь подождать?"

Или "Трудно подождать, что ли?"

Elena, you're completely missing the point. It's not a matter of Почему ты не хочешь подождать, it's about Почему ты считаешь, что неразумно подождать. The person may perfectly be willing to wait, but he thinks it's unreasonable, which boggles the mind of the speaker.

Well, I personally would ask "И что в этом неразумного?" because I'd like to hear the reasons.

Even better!

Я понимаю, перевод верный, но мы по-русски так не скажем

Почему не скажем? Если вам говорят: мне кажется дальше ждать неразумно. То вполне мы по-русски скажем (и говорим): и что в этом неразумного?

А вот вариант: "Мне кажется дальше ждать неразумно. - Почему бы ещё не подожать ?" рисует совсем другую картину диалога.

Мы просто скажем "почему?", и в русском языке это будет то же, что "Что в этом неразумного"

Елена, по-английски-то тоже можно просто спросить "why?" и получить ответ :) Однако это же не значит, что и в русском и в английском люди так ограниченно общаются.

Можно еще подумать, но "неразумно" я бы никогда не сказала. Утро вечера мудренее, если что придет в голову, напишу)

А я бы сказала (и говорю, и от других слышу), и "неразумно" и "бессмысленно", и "нецелесообразно".

Я тоже говорю, но не в таких случаях

Elena, what's so unreasonable about saying something is unreasonable in Russian? 😁

Uly, there's nothing unreasonable about saying something is unreasonable in the right context 😁

Grumbler, your version is good, but it desperately needs the word SO. Otherwise it doesn't sound complete to the English ear.