Check if you can solve a child's example without a calculator

How do you learn to count in your mind? And why do you do that when you almost always have a calculator on hand? The fact is that verbal counting develops thinking. In addition, when you count without the means at hand, you feel a very different level of control of reality.



You know in advance how much change you will be given in the store and whether it is worth stuffing everyone into the elevator if its carrying capacity is 400 kg. The use of a calculator, on the contrary, teaches us to blindly trust a technique whose principle of operation we do not even understand. This dulls our attention and discourages us from thinking for ourselves.

Earlier we shared mathematical secrets and tricks that help multiply and divide in the mind. Today we offer you some test examples. Remember the school curriculum well? Then try to complete our tasks in 15 seconds!

  1. Count without the calculator.
    Add 1000 and 40. Add another 1,000. Now 30. 1,000 again. Then add 20. 1,000 again. 10 more. Solving this problem, try to do all the calculations quickly and in your mind. Do not write or use a calculator. I'm sure the result will surprise you.


  2. How much is it?
    In school, we clicked examples like nuts. But over time, much has been forgotten. For example, does anyone remember how to divide into fractions?


  3. Complicated example and 15 seconds of time
    Solid fractions, and even raised in degree ... The example seems too complicated. But as the math teacher said, any expression can be simplified.


  4. Be careful.
    Wow, negative! I give up. I think I was sick when we went through this.




Answers.
  1. It would seem simple. But the comments suggest otherwise. For some reason, most Internet users have 5,000. And there are those who counted 5100, 4910 and even 2060. At the same time, lawyers gravitate to the last variant of the answer: they say, if there is no word “add” before the number, then it is not necessary to consider it.

    Peels

    Actually, The correct answer is 4100.. 1000 + 40 = 1040; 1040 + 1000 = 2040; 2040 + 30 = 2070; 2070 + 1000 = 3070; 3070 + 1000 = 4090; 4090 + 10 = 4100.. But after 4090, when people add 10, many get 5,000. It seems that in some cases we psychologically try to adjust the answer to a more round number. In others, instead of 90, we remember 900. In short, it is a mindfulness task that we so often lack.

  2. Dividing a number by a fraction is like multiplying it by the same fraction, having previously changed the numerator and denominator places. Any number multiplied by 0 is still 0. Then our example gets a more understandable form: 15 x 10: 3 - 144 = 50 - 144 = -94.
  3. We've sorted out the fractions a little bit already. Multiplication by fraction in the numerator of which the unit is replaced by division by the denominator of the same fraction. Dividing by one second is the same as multiplying by two. The result is: 32:16 + 61 x 2 = 124
  4. It seems that we will have to dust off the forgotten order of mathematical actions. We all taught it in elementary school: brackets, degree, multiplication, division, addition, subtraction. We apply the rule and first put one-fifth into a negative state. To do this, you just need to change the numerator and denominator and erect the resulting number into a square. That makes 25. Then we divide, then multiply and add. 25:25 + 12:2 x 3 = 1 + 6 x 3 = 1 + 18 = 19. Correct answer: 19.



We often resent the fact that school does not teach at all what is useful in real life. Yes, our education system is too outdated and continues to become obsolete every day. But a well-educated person will never get lost in a difficult situation and will be able to find a way out of it.

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