The problem of a wise man who bought and sold a cow, for those who want to test their intelligence

We all know how smart and resourceful children are. Their wit will envy any adult. You don't believe that? Then try to solve the trick problems we've prepared for you. Some of them are confusing adults.



Editorial "Site" He invites you to test your strength and solve children's math problems.

Tasks with a catch

1. Did a man make money selling a cow? Let's start with the first problem. A man bought a cow for $800. Then he sold it for $1,000. Then I bought it again for $1,100. And sold again for $1,300.
   
   
   
   
   
   The task is to figure out whether the man earned, stayed with his or lost money? If you earned or lost, how much? It seems very easy, but think twice before you give an answer.
   
   
2. Numerical puzzle We couldn't leave you with just one task. Therefore, we offer you an interesting font puzzle. Here the numbers are replaced by letters. However, solving the problem is more based on logic. Ready to try your hand?
   
   681575
   
   
   
   
3. Mathematical example for strategists You didn't think math was easy, did you? We invite you to recall school knowledge and solve the following example.
   
   You have four numbers: 5, 5, 5 and 1. By adding, subtracting, multiplying, dividing and bracketing, we get 24 from them, using each of these digits only 1 time.
   
   
   
   
   
   

I think you have thought enough about all the problems. Now is the time to find out if your own reasoning has failed you. To be honest, we didn’t manage everything the first time.

1. The cow problem This problem is trying to catch us twice. First, we want to take the difference between the last and the first amount. That makes 500. But that's the wrong answer. Let's do some simple calculations. Here you need to separately calculate the profit from the first transaction: 1000 - 800 = 200. Then from the second: 1300 - 1100 = 200. In total, it turns out that on all his guns, the man earned $400.. Which we congratulate him on!
   
   
   
   
   
   
2. Numerical puzzle If you have decided this yourself, then accept our sincere congratulations. It certainly wasn't easy. Now let's figure out what the whole point is. So we know that each letter is a separate number. Let's take a look at what addition gives us.
   
   First we will see that O + T , T + O. How can that be? Only if O + T > 9. In this case, O + T = K + 10. It is also likely that T + O + 1 = 10 + O. Given that the addition of two three-digit numbers results in a three-digit number, we can assume within what limits K and T lie.
   
   In other words, K + K + 1 = T ≤ 9. Two conclusions can be drawn from this. First: 1 <= K <= 4. And the second: 2 <= T <= 9. Now let us try to find the value of T. Suppose that T = 9, then O could be 2, but if it is 2, then K = 1. Even taking into account the unit 9 passing from the previous ranks, it does not work, therefore, K must be at least 4. Then T = 9; K = 4; O = 5 (14 - 9). Check: 495 + 459 = 954.
   
   
3. The catch. This problem seems to be the most difficult. I just want to suggest the following option: 5 + 5 - 1 = 24. However, in this case, the condition is not fulfilled. The correct answer is much more complicated: (5 - (1:5)) x 5 = 24. Perhaps you have found another solution?
   
   
   
   
   
   

What can I say, all these trick problems made us suffer. Here it was necessary to recall the order of action in mathematics and connect logic. We hope you've succeeded. You can share the results of your calculations in the comments!