# Problem with batteries

Logic Level 4

We have 8 batteries: 4 good and 4 dead ones. We don't know which is which, as they all look the same. Now, there is a flashlight which will turn on if it's powered by two good batteries. What is the minimum number of tries we need to guarantee that the flashlight turns on?


Clarification: In a try, we place two batteries into the flashlight and see if it works. The flashlight must turn on with the last try.

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