Using としたら・とすれば to ask advice

Question

Is it redundant to give an assumed case and then use the どうすればいい construction?

E.g.

不合格だとすればどうすればいいですか。

If so, what's a better way to express this sentiment?

Answer 1

The sentence:

「不合格{ふごうかく}だとすればどうすればいいですか。」

sounds fairly awkward for using both 「だとすれば」 and 「どうすれば」 back-to-back. If it were grammar that mattered, however, the sentence would be perfectly grammatical. Nontheless, careful speakers/writers would probably not say it that way.

To be honest, the biggest problem that I, as a native speaker, have with this sentence is that I have no idea who it is talking about. Who is the one that might not pass? Who is the one that would/should do something upon finding out about the failure?

You could say:

「（もし）不合格だったらどうすればいいですか/いいでしょうか。」

if you are asking about what you yourself should do.

If, however, you are asking about what the other person should/would do, you might say:

「（もし）不合格だったらどうしますか/どうするつもりですか。」

Answer 2

I think l’electeur explained it in detail.

However, if you quantify X as numerical value and saying “Xだとすればどうすればいい”, now say 不合格 as 40. But other people might believe X as 70 which is regarded as success. In this kind of case, 不合格だとすればどうすればいいですか might work. You are going against other’s evaluation. Say, your family wanted you to go to a big company in Japan. However, you decided to be a musician. In this case, とすればどうすればいいですか works.