"It took six days."
六日 むいか (note that this is not actually a great way to say "six days"!)
If you ask a Japanese person how to say "6 days", I expect they'll answer "muika".
The ６日 in ５月６日 and the ６日 in ６日間 are both read as むいか (muika).
The reading of dates and the reading of time periods are almost always the same, except for １日. For dates it's read ついたち (tsuitachi) and for a time period it's read as いちにち (ichinichi).
One means one day the other means first day. Its the only one that has a seperate word for each.
Not sure why everyone is downvoting you instead of simply pointing out your mistake to you.
Turigamot is correct, if the sentence was "it takes one day", it would be 一日かかります (ichinichi kakarimasu), not tsuitachi.
In this context, would it not be ろくにち, as we're expressing an elapsed period of time, rather than a specific date?
六日 should be presented as one button. So that one can learn the pronunciation むいか. It doesn't help to hear ろく and ひ。
No , Ron is right. ついたち is used for the first day of a month etc where as いちにちい is one day
六日かかります (muika kakarimasu) - It takes 6 days. This sentence is counting days, not saying that it is the 6th of the month. If we're counting days, then it should be いちにち, not ついたち.
You are rught but both 六日 and 六日間 are fine for this sentense. I def use 六日 myself. You have to use 間 when you use the words 'weeks' or 'hours' like 一週間 or 二時間 but you don't need for 'seconds', 'minuets', 'months' and 'years' as 10秒、5分、3ヶ月、４年 even when you talk about the length or period of time(^o^)