In January 8, 2015, the club launched"How to use less than 15L of water, 3 liters of water from the pond with 2 kettle"Challenge the classic logic interview questions, there are nearly 100 members to participate in online interaction, and put forward a variety of new ideas. In the traditional two barrels each pour ideas, there are a lot of students proposed the principle of buoyancy, filling principle, method of marking, pulley, lever principle, free falling principle, time principle, combined with the mathematical knowledge, try all kinds of different solutions. It can be said that all roads lead to Rome! The event and a time to see the students thinking about the problem of diversity and differences in thinking.

In this order and workable ideas and carries on the contrast analysis, to find the optimal solution, and tries to through the phenomenon eventually see the essence.**Hope that every person in the process of discovering the problem solving process, can be able to break, dare to innovate, dare to try new methods. You will find that you can have a harvest in every way that leads to Rome, which is far better than a fixed result, and can enrich your experience and help you grow.**

**If there is a pond, there is an infinite number of water. The existing 2 empty water bottles, the volume of 5 liters and 6 liters. The problem is how to get 3 liters of water from the pond with these 2 water bottles.**

This is the most basic way to achieve, without the aid of any external tool, do not consider the shape of the pot is the rule, not to consider the use of water saving. The method accords with the original title too observant of conventional standards..

It is obtained by using the method of marking the water height by marking the 1L height of the bucket wall (inner wall or the outer wall, a wooden stick), and obtaining the final 3L water for 3 1L water. In case the outer wall is marked, the bucket needs to be transparent or semi transparent; the diameter of the barrel can be allowed to enter into the case of the mark.

It is similar to the measurement method of "Cao Chong", using 1L water in the water in the water, the way to make a mark on the outer wall of the barrel. This method does not require the use of any external tool, the shape of the bucket is not required, the overall water consumption. The bucket can float in the water, if it is filled with water.

It imitates the story of "the crow drinking water", the use of non absorbent filler, access to 3L of water. The method needs to be realized by external props, and it is feasible in theory.

This method obtains 3L water by means of a hole in a hole with the same diameter as the same as the bottom of the barrel.

Although the method is novel and unique, it belongs to the destructive one time solution, although the theory is feasible, but it is not advocated in practice.

This method obtains the capacity of 3L water by calculating and adjusting the balance of lever. With external tools, and with mathematical calculations to obtain the desired results. Process of mental and physical coordination.

This method is used to measure and calculate the flow velocity and obtain the required 3L water. Although theoretically feasible, but the actual operation is not strong, is an ideal solution.

This method uses the water's volatility principle to obtain the required 3L water by observing and measuring the time. Although theoretically feasible, but the environmental requirements are too high, the actual operation is not strong, is an ideal solution.

Through the research on the method of all the students, it is found that the optimal method is still the best.**Method 1**.

The principle of 15L is 5+5-6+5-6=3, the principle of 18L is 6-5+6-5+6-5=3. If you don't use any tool, it's the best way to do it. Because the volume of the two containers is the largest is 11, adjust the position of any two number is more than 11 or less than 0. So if it is strictly in accordance with the original intention of the answer, there will be no unexpected answer.

But the highlight of the event is that it inspires the students' divergent thinking and innovative thinking, jump out of the inherent thinking, and can be combined with other theories of common sense and life, the courage to express their views and discuss interaction with others.

**Hope that every person in the process of discovering the problem solving process, can be able to break, dare to innovate, dare to try new methods. You will find that you can have a harvest in every way that leads to Rome, which is far better than a fixed result, and can enrich your experience and help you grow.**