### Brain Teasers

# Columns

There are two columns, both 100m high (both heading straight up from the ground). A rope is tied to the tops of both columns. The rope is hanging freely and its length is 160m. The lowest point of the rope is exactly 20m from the ground. What is the distance between the two columns?

### Hint

Draw a picture... and remember no difficult math calculation is needed.### Answer

The distance is zero. The lowest point of the rope divides the rope in half, i.e. 80m each. If you add 80m plus the distance from the ground which is 20m, you get 100m, so the rope must be going straight down...Hide Hint Show Hint Hide Answer Show Answer

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## Comments

actually, if you want to get technical,it would be slightly less than 80m because it still has to loop around.

ya right the distance between the columns would be 2wice the thickness of rope

I liked it. It drove me crazy for a very long time, i finally gave up and looked at the answer.

nice one! good job.

i cant remember the formula though if the columns are actually apart from each other.

i cant remember the formula though if the columns are actually apart from each other.

I was disappointed when I saw that the answer was trivial as the problem looked like it would have been fun to solve.

I also came up with twice the diameter of the rope as the answer since zero doesn't allow for the rope to hang freely.

I also came up with twice the diameter of the rope as the answer since zero doesn't allow for the rope to hang freely.

Maybe a trick rather than Mathematics. I was starting to think exponential equations of catenaries but the hint said no complicated calculations required. I think it's a fair teaser for the trick category!

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