Logic tasks. Brain Workout

Would you like two simple puzzles that can amuse a group of friends and just stretch your brain well? We and the BigIdeas project have a couple for you. Read it!

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Steel balls

This task is great for "breaking off" people with a technical mindset who consider themselves cool engineers and specialists in everything mechanized. The task sounds extremely simple:

How much does a thousand steel balls with a diameter of one millimeter weigh?

Usually the answers to this question vary within one or two tons. In fact, a thousand millimeter steel balls weigh 3.7 grams.

In order to find the answer to this question logically, without using mathematics, it is enough to know the following:

• The density of steel is 7.7 grams per cubic centimeter.
• A thousand steel balls can easily be placed in a cubic sanimeter.

This means that a thousand balls cannot weigh more than eight grams, and, in fact, it weighs much less (if we take into account the gaps between the balls). Of course, there can be no question of any tons or even kilograms.

50 folds

The next task sounds even simpler than the first:

"Imagine that you take a piece of paper and fold it in half, then in half again, and then again and again — just 50 times. How thick will a piece of paper folded in this way be?

There are two tricks in this problem:

• Firstly, it is impossible to fold a piece of paper 50 times — the maximum that a person is capable of is 11 bends, and no more bending (in fact, it all depends on the size of the paper — here is an article in the Wiki).
• Well, secondly, if you just imagine how thick a piece of paper folded in half 50 times can be, you will get a truly astronomical figure - more than 83 million kilometers. This is more than half the distance from the Earth to the Sun.