The owner of the architectural firm showed problems with matches, which gives at the interview Bashny.Net

Matches have long been used to train logic and thinking. Forget the computer, the phone, or even the pen and paper. After all, such examples can be called “solved with hands”. Shift, add and remove matches to get the specified figures, you can on any fairly flat surface.



Even a child can do this. But as it turned out, some simple tasks suddenly become a barrier even in the way of adults with higher education degrees. What is the total length of all matches used to build a figure in the photo, if its area is 300 square centimeters? It seems like a simple question, but the owner of the architectural firm, who uses it in interviews, is not sure.

So we have a figure made up of sticks of the same length. The area of the entire painted figure is 300 square centimeters. It is required in 3 minutes to determine the total length of all sticks.



It seems like nothing complicated: third grade, second quarter. But, sadly, half of the candidates are eliminated, having failed to solve this elementary example in the allotted time.



Well, think for yourself first. There's no big catch here. You just need to connect logic and be attentive to the little things. If it doesn’t work, read on.

Solving the problem Where to start? They say that choosing the right method is half the solution. And any difficult task can be presented as a little simpler. Following this plan, try to break the figure into small squares and count their number.



Phere Po two on four sides and (include logic) four inside. Total 2 * 4 + 4 = 12 squares with a side in one match.

We know that their total area is 300. So the area of one square is 300 / 12 = 25 square centimeters. Knowing the area of the square, it is easy to determine its side. In our case, it is 5 centimeters.



The sides of the inner square are formed by external walls. One of them is shared by each of the two. Therefore, it will be easier to count rectangles, each of which consists of 7 matches. 7 * 4 = 28 matches used. Multiply 28 by 5 and get that the total length of all matches is 140 centimeters.



You might say that the problem is simple and has nothing to do with real work. But in business, it is often necessary to calculate options without departing from the phone to achieve the most economical option without sacrificing quality. And here logic and the ability to think is very necessary.