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Burning Time

The Puzzler


RAY: This was submitted by Paco Jain and it's from my Space and Time Series, though it had nothing to do with space, and just a little bit to do with time. Here it is:

Do you remember those old Westerns on TV where the bad guys would try to blast the door off the bank vault with dynamite? They would strategically locate the explosives and then light a fuse, which had a long enough burn time to allow them to get a safe distance away before the blast? Well this is about those kinds of fuses.

Imagine that you have two lengths of fuse like that and each takes exactly 1 hour to burn. But the fuses don't burn evenly and they're both likely to be different. So let's say a fuse is 1 foot long and it takes 40 minutes for the first inch to burn and then only 20 minutes for next 11 inches to burn. Or it could be 12 minutes for the first 4 inches and 48 minutes for the last 8 inches to burn. All you know is that the fuses are not identical and that they each take 1 hour to burn completely.

Now using only these two fuses and a cigarette lighter, how do you measure 45 minutes?

Think you know? Drop Ray a note!

[ Car Talk Puzzler ]

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