Aptitude - Average - Discussion

The age of mother and father when the child was just born is 24/2=12.
When the child reaches to the age of the mother means when it will reach 12 years,
Father age is 12+12=24.

Can anyone say is this answer is correct?

Thank you for explaining the answer.

3 year ago(h+w+c) = 27 * 3 = 81.
5 year ago=81-6 = 75(2h+2w+2c).
5 year ago(w+c) = 2 * 20 = 40.
5 year ago h = 75-40 = 35.

And the present age is 40 years of the husband.

First separate the question:

In the first part, The average age of husband, wife and their 3 years ago was 27 years, so;

Lets consider Husdand age = x-3(-3 because it was 3 years ago from the present age)

Wife's age= y-3 and son's age = z-3,
Average= x-3+y-3+z-3/3=27,
x+y+z=81 ------> (1)

Second part of the question.
That of wife and the child 5 years ago was 20 years, so;
Wife age years ago is y-5,
Sons age is z-5,
Avg= y-5+z-5=20,
y+z=30---> (2)

Equating (1) and (2)
Then x=40.

The average age of a husband and wife at the time of their marriage was 25 years. A son was born to them exactly 2 years after their marriage and the average present age of all three is 24 years. How many years have been passed by the couple?
Can anyone explain the answer of this?

27*3=81,
81+9=90,
5year ago =formula( average age*2),
So, 20*2=40,
40+10=50.
Husband age 90 - 50 = 40.

@Kanchan Shah.

Can you give the explanation little briefly?

Your explanation is superb, Thanks @RAMYA.

The average age of three persons is 18. If two of them are included then the average age becomes 20. If the age of 1st is 17 then find the age of the remaining persons.

Can anyone tell me?

@All.

Take x, y, z intial age is 27 after three years it converted into 30. For three members it is 90.
Then 5 years back 20 years. Calculate with present age it is 25.

Now
X+Y+Z=(3*30)=90.
Y+Z=20(5 years back)Now =(25*2)=50,
Now equate it.
Y+Z cancelled,
X=90-50.
And X=40.