Aptitude - Problems on Ages - Discussion
Discussion Forum : Problems on Ages - General Questions (Q.No. 15)
15.
The age of father 10 years ago was thrice the age of his son. Ten years hence, father's age will be twice that of his son. The ratio of their present ages is:
Answer: Option
Explanation:
Let the ages of father and son 10 years ago be 3x and x years respectively.
Then, (3x + 10) + 10 = 2[(x + 10) + 10]
3x + 20 = 2x + 40
x = 20.
Required ratio = (3x + 10) : (x + 10) = 70 : 30 = 7 : 3.
Discussion:
77 comments Page 2 of 8.
Shiva said:
9 years ago
What is the meaning of fathers age will be twice that of his son?
2(3x + 10 + 10) = (x + 10 + 10).
Why are you taking?
(3x + 10 + 10) = 2((x + 10) + 10).
Please tell me.
2(3x + 10 + 10) = (x + 10 + 10).
Why are you taking?
(3x + 10 + 10) = 2((x + 10) + 10).
Please tell me.
(1)
Santash Kumar Jena said:
9 years ago
10 years ago:
Son = x - 10,
Father = 3 (x - 10).
10 years hence:
Son = x + 10.
Father = 2 (x + 10).
Equating the age of the father at hence 10 years, so we have to add 20 in the past 10 years.
So,
3 (x - 10) + 20 = 2 (x + 10),
3x - 30 + 20 = 2x + 20,
3x - 2x = 30 - 20 + 20,
X = 30.
Now for present ratio, we will add 10 to past equation.
So,
3 (x - 10) + 10 : x - 10 + 10,
3 (30 - 10) +10 : 30 - 10 + 10,
3 (20) + 10 : 30 = 70 : 30,
7 : 3.
Son = x - 10,
Father = 3 (x - 10).
10 years hence:
Son = x + 10.
Father = 2 (x + 10).
Equating the age of the father at hence 10 years, so we have to add 20 in the past 10 years.
So,
3 (x - 10) + 20 = 2 (x + 10),
3x - 30 + 20 = 2x + 20,
3x - 2x = 30 - 20 + 20,
X = 30.
Now for present ratio, we will add 10 to past equation.
So,
3 (x - 10) + 10 : x - 10 + 10,
3 (30 - 10) +10 : 30 - 10 + 10,
3 (20) + 10 : 30 = 70 : 30,
7 : 3.
(1)
Paritosh said:
8 years ago
If we assume x=10,y=40,it satisfies the given condition And we get ratio as 5:2
is it correct?
is it correct?
(1)
Rohini Priya said:
7 years ago
Here they considered ages 10 years ago 3x and x, these are not present ages.
Since we solve all problems by having present ages we convert them to the present age.
So the present ages will be 3x+10 and x+10.
Since we solve all problems by having present ages we convert them to the present age.
So the present ages will be 3x+10 and x+10.
(1)
Sanjay said:
8 years ago
Thanks for all the solution.
(1)
Shruti iyer said:
8 years ago
Akash said to Akansha when I will be 4 times your present age you will be 3 times my present age. If Akash is 4 years older than Akansha find the sum of their present ages?
Can anybody solve this with a shortcut method, please?
Can anybody solve this with a shortcut method, please?
(1)
Prakash said:
4 years ago
Thank you @Nagu.
(1)
Pammy said:
6 years ago
@Archi simple why they have taken minus means 3x is 10 year ago.
3x+10 present age.
3x+10 +10 means 10 years after present age.
3x+10 present age.
3x+10 +10 means 10 years after present age.
(1)
Gimid-pussi said:
5 years ago
Required ratio = (3x + 10) : (x + 10) = 70 : 30 = 7 : 3.
Anyone explain this step in detail.
Anyone explain this step in detail.
(1)
Yhxyc said:
8 years ago
Thanks everybody for the given explanation.
(1)
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