Aptitude - Average - Discussion

@Anwi.

40/0.5 = 80 man = 80*11/16 = 55 and son's age = 80-55 = 25.

Whether the answer & method is right or wrong explain anyone?

The average age of man and son is 40 years. The ratio of their ages is 11:5 respectively. What is the son's age ? Solve it.

((65+72)+(60+70)+(68))/5 = 67.

Logic Concept:

Let Arun age is X.
In Arun's opinion: 65 > X < 72.
Possibilities: 66, 67, 68, 69, 70, 71.

In Brother's opinion: 60 > X < 70.
Possibilities: 61, 62, 63, 64, 65, 66, 67, 68, 69

In Mother's opinion: X <= 68.
Possibilities: 1, 2, 3......61, 62, 63, 64, 65, 66, 67, 68.

Now check what similar terms are matching in every 3-possibilities i.e 66, 67, 68.

To find Average age = (66+67+68)/3.

Note: 3 = Three possible values. It is not Arun+Brother+Mother at all.

65 - 72 -(1) : 68.5.

60 - 70 -(2) : 65.0.

68 -(3) : 68.0.
-------
201.5/3 = 67.

Arun says that his age is > 65 but < 72
Therefore his age in between 66 to 71.

View of his brother, Arun's age is >60 but < 70,
Therefore Arun's age in between 61 to 69.

View of his mother, Arun's age is Cannot be > 68,
That means Arun's age under 68 years only.


The above three members opinions Arun's age in in between 66 years to 68 years,

Then (66+67+68)/3.

I got ans like tis way..., may i dont know whether is it correct r nt
view of arun avg=(65+72)/2=68.5
view of his brothers avg=(60+70)/2=65
view of his mother taken as=68
Therefore the avg of above three as=(68.5+65+68)/3=67

His mother's view is that his weight cannot be greater than 68 kg
but she cant said that >=68
so the solution is 66+67/2=133/2=66.5
answer is none of these..

Arun-65+72/2=68.50
brother-60+70/2=65.00
mom- 68.00
total
=201.50/3= 67

I don't understand anyone explain again.