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To earn his wand, Harry was given 4 rope...

To earn his wand, Harry was given 4 ropes and a lighter. Each rope burns at a non-con- stant rate but takes exactly one hour to burn completely from one end to the other. Harry can only light the ropes at either of their ends but can decide when to light each end as he sees fit. The goal is to use the ropes to measure time. For example, the time taken to burn one rope if burnt from only one end is 1 hour. So 1 hour can be measured using the ropes. Similarly, at max, how many lengths of time can be measured using these ropes? The right answer earns him his wand.

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