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There is a well as shown in figure. A stand is present in the middle of the well and man is standing on the stand. The height of stand is the same as the depth of well. The distance between the boundaries of stand and well is 1.1 m. The man is provided with two rods of 1 m each.The man has to come out of the well using the two rods. How is this possible? Solve it out.

enter image description here

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  • $\begingroup$ Welcome to Puzzling! This is not a [logic-puzzle]: that tag is only for puzzles which require logical deduction. I've removed it for you. $\endgroup$ – Deusovi Aug 3 '16 at 6:04
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    $\begingroup$ Similar (possibly duplicate): puzzling.stackexchange.com/questions/15706 $\endgroup$ – f'' Aug 3 '16 at 6:20
  • $\begingroup$ If you're confused by the exposition, picture "an island ringed by lava." The diagram shows the situation from above. The depth of the well is not important, all the action happens in the plane. $\endgroup$ – Colonel Panic Aug 3 '16 at 10:14
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    $\begingroup$ It's not possible, by which I mean that the sticks offer no advantage. The man can get from the edge to the centre, but not from the centre to the edge. Equally, the rods would need considerable bearing, otherwise they would roll off when under deflection. I don't think you've thought this through ;-). In fact, if the radius of the stand is larger than ca. 150mm, it doesn't work anyway! On the other hand, it is of course easy to cover 1.1m from a standing jump. $\endgroup$ – Strawberry Aug 3 '16 at 11:03
  • $\begingroup$ @Strawberry: I make 0.2m the point where the central radius is such that the sticks are the exact length they need to be (ie ignoring the fact that they'd need some overlap, etc.) Also you could attach the sticks to one another to create a single placable item if you were in the centre. You don't need to place the outer one first. $\endgroup$ – Chris Aug 3 '16 at 12:31
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The basic idea:

enter image description here

Calculation:

He places one of the rods on the well boundary, so that its both end is laying on the boundary, but the middle is above the well itself (the vertical rod on my picture). The middle of this rod is $\sqrt{(1.1^2-0.5^2)} \approx 0.98$ meters away from the stand, thus he can lay the second rod with its ends at the stand and the middle of the first rod, and walk out on them.

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    $\begingroup$ Correct obviously, but how do you do that? I would just jump it after both of my sticks fell down the well. :) $\endgroup$ – user21939 Aug 3 '16 at 9:21
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    $\begingroup$ yes, unless we don't assume the man's arms are long enough this is much more a method about how to get to the stand in the middle. $\endgroup$ – elias Aug 3 '16 at 9:27
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    $\begingroup$ @elias that ocurred to me too. Perhaps there's treasure on the island you want to reach. $\endgroup$ – Colonel Panic Aug 3 '16 at 10:15
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    $\begingroup$ No, @Jasen. The 1.1m given is not the radius of the well, but the distance between the stand and the well boundary, as the question states. $\endgroup$ – elias Aug 3 '16 at 11:16
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    $\begingroup$ The distance from the edge of the stand to the edge of the well is 1100m. This means that the radius of the well must be more than 1100m. So, let's say the stand has a radius of 250mm, and the well therefore has a radius of 1350mm. Under these circumstances, an isoceles triangle of base 1m and height 1m could not touch two points on the wall of the well, and reach the stand. $\endgroup$ – Strawberry Aug 3 '16 at 11:18

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