Incense sticks problem.

A Sufi monk got an errand from his teacher: to meditate for exactly 45 minutes. He has no watch; instead he is given two incense sticks, and he is told that each of those sticks would completely burn in 1 hour. The sticks are not identical, and they burn with variant yet unknown rates (they are hand-made). So he has these two sticks and some matches: can he arrange for exactly 45 minutes of meditation?

Source: Univ. of Utah

Please put answer in spoiler tags.

Quote: Wizard

they burn with variant yet unknown rates (they are hand-made).

I assume variant means the rate varies from one stick to another. Not that different sections of the sticks burn at different rates.

While I am here, www.adventofcode.com might be of interest to coders or people who like to solve puzzles with code.

I currently have 17 stars from a possible 24. I'm pretty sure there's some I've not done that are beyond my current capabilities (and time). Though I did enjoys todays challenge.

Quote: TheCesspit

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Light stick A at both ends.
Light stick B at one end.

When Stick A burns out (30 minutes), light the other end of Stick B. Stick B has 30 minutes left, halved = 15 minutes more left. 30+15 = 45 minutes.

I have to admit that I never thought of this way. OTOH I did get how to put 4 gallons of water in a 5 gallon jug so I am going tonchalk this to
I thought said sticks burned like sparklers and just go to my days work.

Exchange the incense sticks for a cheap watch?

Or use the timer on the cell phone. Or the one in the oven, or the microwave.

Quote: Wizard

A Sufi monk got an errand from his teacher: to meditate for exactly 45 minutes..

Get a new Sufi monk. Realize that meditation is an act that should not be precisely measured or timed in an arbitrary manner. Realize that incense is a distraction to the meditation, not an enhancement or a requirement, let the programmer contemplate his navel rather than his code.