पाँच घंटे लगते हैं

You use this to answer the question 'How long?'. Just place the duration at the start. The verb lagte hain changes based on the subject. Since ghante (hours) is plural and masculine, we use lagte hain. If you were talking about one hour, you would say ek ghanta lagta hai. It is like building with blocks.

Use it when discussing travel times between cities. Use it when explaining how long a movie or a cricket match lasts. It is perfect for telling a friend how long your cooking takes. It works well in professional meetings for project timelines. Use it when you are stuck in traffic and complaining to your spouse.

Do not use it for a specific point in time. If you mean 'It is five o'clock', say paanch baje hain. Do not use it for a one-time past event. For that, you would say paanch ghante lage. Avoid using it if you are talking about people 'taking' things physically. This is strictly for time, effort, or resources.

In India, time can be a bit 'flexible'. When someone says paanch ghante lagte hain, they might mean five hours or six. It is often an estimate rather than a stopwatch calculation. Traffic in cities like Mumbai or Delhi makes this a very common phrase. You will hear it at bus stands and train stations constantly.

You can swap the number easily. Do ghante for two hours or dus minute for ten minutes. If you want to say 'it will take', use lagenge. If you want to say 'it took', use lage. Adding kam se kam (at least) at the beginning is very common. For example: Kam se kam paanch ghante lagte hain.