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#1 unreality

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Posted 30 August 2007 - 07:06 PM

Mother makes tasty toast in a small pan. After toasting one side of a slice, she turns it over. Each side takes 30 seconds.
The pan can only hold two slices. How can she toast both sides of three slices in 1 & 1/2 instead of 2 minutes?
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#2 Martini

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Posted 30 August 2007 - 07:22 PM

The only solution I can come up with is that she splits the third slice down the middle and makes two thinner slices out of it and puts both original sides face down on the pan. Not sure if that violates any conditions of your riddle since there are actually four slices now though.
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#3 unreality

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Posted 30 August 2007 - 07:52 PM

Nope. All the toast stays full.
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#4 rookie1ja

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Posted 30 August 2007 - 08:08 PM

Was it meant to be this easy?
Spoiler for Solution

Have I missed anything?
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#5 unreality

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Posted 30 August 2007 - 09:28 PM

She puts two slices in the pan; after 30 seconds she has toasted one side of each. She turns over the first slice, takes the second from the pan, and in its place puts the third slice. After the second half minute the first slice is done and the other two are half done. In the last 30 seconds she finishes the second and third slices.

Yep. It's that easy. But lots of people miss the solution. I did. (And Martini did)

It's automatic assumption that you have to toast each piece entirely...
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#6 Martini

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Posted 30 August 2007 - 10:17 PM

Yep. It's that easy. But lots of people miss the solution. I did. (And Martini did)

It's automatic assumption that you have to toast each piece entirely...


Actually, it did cross my mind. But I thought the point of the riddle stating "After toasting one side of a slice, she turns it over" was to add the condition that putting any slices aside for later toasting wasn't an option.
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#7 bonanova

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Posted 30 August 2007 - 10:36 PM

I got here too late to get my answer in, but here's my reasoning without reading what must be the only solution:

[1] There's enough time to get the job done.
[2] If you do two slices in the first two time slots, you lose - cuz you cant do both sides of the third slice at the same time.
[3] So you have to involve the third slice during the 2nd time slot.
[4] Then there's only one possibility for the 3rd time slot, and it's the answer.
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#8 Duh Puck

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Posted 24 January 2008 - 12:04 PM

Good problem. Simple, yet not obvious ...

Spoiler for solution ...

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#9 unreality

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Posted 25 January 2008 - 06:42 PM

Yep you guys all nailed it ;D
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#10 funandatraveler

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Posted 10 February 2008 - 07:01 PM

How bout toasting one side of two slices=30 seconds, then remove one slice (already toasted on one side), toast the other side of one slice (completely toasted now) and the one side of piece number 3=1 minute, now take the completely toasted piece out and replace it with the piece that is toasted on one side (placing the untoasted side down) and flipping the piece that is already in the pan=1.5 minutes and both sides toasted. There was probably an easier way to explain it but I think that does it.
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