Question 976631
.
10 years ago man's age was 6 times the age of his son. 12 years later, the age of the son will be 27 years.
what is the present age of the father?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~



        The solution in the post by @lwsshak3, giving the answer 100 years for the father's age, is absurdist and incorrect.
        The cause of the mistake is that @lwsshak3 lost the logic line on his way.


        I came to bring a correct solution.


        The problem itself is extremely simple and can be solved mentally, without using equations.


        When I was in front of dilemma "what to provide - a routine algebra solution 

        or a shining mental solution" - I could not resist and chose a shining mental solution.



<pre>
The problem says "12 years later, the age of the son will be 27 years."

This means that the current age of the son is 27-12 = 15 years.


Hence, 10 years ago the son was 15-10 = 5 years old.


At that time, the father's age was 6 times the sun's age, i.e. 6*5 = 30 years.


Hence, the present age of the father is 30 + 10 = 40 years.


<U>ANSWER</U>.  The present age of the father is 40 years.
</pre>

Solved correctly in the form accessible for a 4-th grade student
to teach him to build a logic line and to keep it firmly.


It is the way, how a responsible teacher should teach,
if he wants the seeds he sowed produce right shoots.



/////////////////////////////////



I said earlier in one of my posts that the method which @lwsshak3 regularly uses is a computer code.
This problem, solved incorrectly by @lwsshak3, remarkably confirms this my hypothesis/observation.
@lwsshak3 made a rude OBVIOUS error, but yet he did not even waver, showing total absence of a normal human reaction.


It is why such "teachers"/"tutors" are dangerous participants of an education process - 
because they have no built-in function of self-checking,
as well as they have no feeling of responsibility for their production.  
Their only goal is to occupy as much territory as possible.


It is just as if sappers were laying mines in the path of their own army's advance.