# Tricky Logic Problem?

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OK, here we go folks:

I am standing in front of a machine. It has 3 cogs on it, with the numbers 1 to 3 printed in a clockwise fashion. The cogs also turn clockwise.

The machine has two levers, one on the left and one on the right. When I pull the one on the left, the bottom 2 cogs advance to the next number. When I pull the one on the right, the top two cogs advance similarly.

All 3 cogs currently show the number 3. How do I change that to 2,2,1 reading from top to bottom ? There are a total of 9 pulls of the levers. I believe it has to be done in 8.

What is the combination of left and right pulls to get me to 2,2,1 ?

Many Thanks !!!
I don't think it's possible.

Look.

The cog in the middle must advance 2, 5 or 8 times in order to show the "2".

This cog will advance each time you pull any of the levers. Let's then assume that the lever shoud be pulled 8 times.

The top cog must advance 2, 5 or 8 times in order to show the "2".

The bottom cog must advance 1, 4 or 7 times in order to show the "1".

Now, we should be able to add the number of times the top cog must advance to the number of times the bottom cog must advance and the result should be 8. Not possible, I'm afraid.

So, what's tricky here?

Can I pull two levers at a time?

rgds,

cairn
There is no solution to this problem! We invite you to pose your solution, which obviously is incorrect.

Anonymous
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Read the problem again, you're wrong - the cogs turn clockwise. The middle cog must advance 1, 4 or 7 times in order to show a "2". And so on...
AnonymousRead the problem again, you're wrong - the cogs turn clockwise. The middle cog must advance 1, 4 or 7 times in order to show a "2". And so on...

Forgot to add - I imagine the numbers are actually ON the cog, so that when it moves clockwise, it shows the previous number.
That problem gave me a hard time to solve when I played that game too. You have to grab the lever and hold it down, this will cause the middle cog to keep turning, which will allow you to reach 2,2,1.
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