Aptitude - Problems on Ages - Discussion

@All.

By using using Option Verification method.

Option: A)4.

Step1: consider young child=4
Step2: Try to confirm.

Add the numbers of 5 children in the difference of 3.
child1= (1,2,3) 3 times differ and age is 4
like that, we do all the steps.

Child2= 8, child3= 12, child4= 16, child5= 20.
add=4+8+12+16+20=60.
split 3 times=20+20+20=60.
The difference is =20.
so we have to divide = 20/5=4.
Answer is 4.

Take option: B)8.

Add: 8 + 12 + 16 + 20 + 24 = 80,
can't split 80 in 3 times.
So this option is wrong.

option: C)10
Add: 10+14+18+22+26=90
Split 3 times: 30+30+30=90
The difference is = 30
So we have to divide = 30/5 = 6.
5 is nothing but it is many children.
But in the option, there is no value 6.

So, Finally: option A)4 is correct.

There are 5 children. Each is borned in 3 years gap.
It means age of childrens.

Let assume age of first children is x year.

Hence, age.

1st child is : x.
2nd : x+3.

3rd : x+6 i.e.(x+3+3) (simply 3rd child is born after 3 years from the birth of 2nd child).

Similarly,
4th child age : x+9.
5th child age is: x+12.

If we add all children age together.

x+ (x+3) + (x+6) + (x+9) + (x+12) = 50 (it is given in question The sum of ages of 5 children born at the intervals of 3 years each is 50 years. ).

By adding all x together and all numbers it comes.

5x + 30 = 50.
5x = 20(50-30).
x = 4(20/5).

Hence the age of all kids.

1st: x = 4 year.
2nd: x+3 = 4+3 = 7 year.
3rd: x+6 = 4+6 = 10 year.
4th: x+9 = 4+9 = 13 year.
5th: x+12 = 4+12 = 16 year.

For all who don't understand here is the simple explanation.

Let the last child ( 5th ) born be x years old,
3 years before the 4th child was born so his age has to be x+3,
now the 3rd child was born 3 years before the 4th child. so the age of 3rd child is 3+3 ie 6+x.
so on..we get
x ( last child ) + x+3 ( a child before x )+ x+6 + x+9 + x+12 =50.

so x+x+x+x+x + 3+6+9+12 =50
5x + 30 =50
5x = 50-30
5x = 20
x = 4.
where x is the youngest child.

Explanation in Hindi: :P
jo last baccha hua uski age x hai...jo usse 3 saal pehle paida hua hoga toh uski age to x se 3 saal badi ho hogi na...so x+3,
so usse 3 saal pehle hua hoga uski age x se 6 saal badi and so on.

Let the X be the first or Oldest Child born to Uncle “Bhokal”.

Since All the child is born at 3 years later than their elder Siblings
Therefore sequence will be
X( eldest Child)
X-3
X-6
X-9
X-12( youngest Child)
So, finding X value does not mean the youngest child rather it’s the age of the eldest child

Now, as per the question,
Total age of Children = 50
X+X-3+X-6+X-9+X-12=50
Total X’s + Total Numbers= 50
5X-30=50
5X= 50+30
X=80/5
X=16 (Eldest Son Age)
Since Youngest Child came 12 years later than his /her eldest sibling.
So youngest child= X-12= 16-12=4 years

Lets assume that the first elder son age is X, then the difference in the age of 3 years among the consecutive child summing to the total age of 50 would be follow.Here (X-3) corresponds to 2nd elder child age and (X-6) corresponds to 3rd elder child age and so on

x+(x-3)+(x-6)+(x-9)+(x-12)=50 ----> (1)
5x-30=50
5x=80
x=16

The (x-12) in equation 1 corresponds to 5th child age and by substituting X = 16 & (X-12) = Y in equation 1 we ill get 5th child age as below

16 + 13 + 10 + 7 + Y = 50
46 + y =50
Y = 50-46
Y = 4

Hi guys,

The best easy way to solve this type of question : You can go as per options and we can reduce the time consumption.

Go as per 1st option : for 1st child if 4 years then 2nd child 4+3 =7 years, Similarly 3rd child 10 years, 4th child 13 years and 5th child 16 years.
Then,
Add all the years if u get total 50 years (given in question) you decide your answer is correct. No need to calculate we can reduce our time for this type of easy question.

Children age+interval 3
5 ---> x
4 ---> x+3
3 ---> (x+3+3)=x+6.
2 ---> (x+6+3)=x+9.
1 ---> (x+9+3)=x+12.

Sum of their age is 50.
x+x+3+x+6+x+9+x+12=50.
5x+30=50,
5x=50-30,
5x=20,
5x=20,
----------
5
x=4.

Let's check:

Eldest (1) (x+12)--4+12=16
Next (2) (x+9)--4+9=13
Third(3) (x+6)--4+6=10
Fourth(4) (x+3)--4+3=7
Youngest(5) (x)--4

Take note:
There is an interval of 3 years.

I have an other way to solve it.

When 1st baby came and he became 3years old than other baby came. When 2nd baby became 3years old than 3rd baby came and 1st baby became 6years old like it 3x4 = 12, so 1st baby became 12 years old than 5th baby came 1st baby became 15 years old.

Like, 1st 15 2nd 12 3rd 9 4th 6 5th 3,

3+6+9+12+15=45 thair is 5 years. So give one year.

It will be.

4+7+10+13+16=50.

We can take the youngest child as x.

Hence, 1st child = x.

2nd = x+3.
3rd = x+6.
4th = x+9.
5th = x+12.

Therefore, x + x + 3 + x + 6 + x + 9 + x + 12 = 50.

5x + 30 = 50.

5x = 50 - 30 (remember the sign changes when you transpose or change the side).

5x = 20.

x = 20/5 (remember the sign changes when you transpose or change the side).

x = 4.

So, the age of youngest child = 4 years.

Step 1:Let x be the age of the youngest,
Step 2. Write out the equation,
x + (x+5) + (x+10)= 60,
Step 3: Isolate the variable x,
x+x+x+5+10=60,
3x+ 15 = 60,
3x= 60-15,
3x = 45,
x = 15 (present age of the youngest),

To find the age of the youngest five years ago we can use this expression ,
(x-5). Therefore, the age of the youngest five years ago is 10, since 15-5=10.