Renting something for half an hour and returning it after 5 minutes

Question

Question: When bicycles are rented out, there is a condition that money for at least half an hour will be charged, even if it is returned after only 5 minutes, and people generally agree to this. Is it then permissible to charge this surplus rent for 25 minutes or not?

Answer

The contract was made for half an hour; the hirer, having met his need in 5 minutes, returned the bicycle of his own accord and paid the rent for half an hour — this is proper.

Source: Fatawa Mahmudiyya

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