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.
Bibek paudel said:
3 years ago
@All.
Here's my explanation.
Let's take the present age of
Son= s
Father =f
10 year before,
son= s-10.
father= f-10.
Equation i
3(s-10)=f-10
3s-f=20 --> (i)
After 10 year;
son=s+10
father= f+ 10
equation (ii)
2(s+10) = f+10
2s-f = -10 --> i)
By equation;
S = 30
F = 70.
So, the ratio = 7:3.
Here's my explanation.
Let's take the present age of
Son= s
Father =f
10 year before,
son= s-10.
father= f-10.
Equation i
3(s-10)=f-10
3s-f=20 --> (i)
After 10 year;
son=s+10
father= f+ 10
equation (ii)
2(s+10) = f+10
2s-f = -10 --> i)
By equation;
S = 30
F = 70.
So, the ratio = 7:3.
(76)
EncodeMaster said:
1 decade ago
Let Father = F and Son = S.
10 Years Ago:
F-10 = 3(S-10).
F = 3S-20 ------ (i).
10 year hence:
F+10 = 2(S+10) ------ (ii).
Replace (i) in (ii).
3S-20+10 = 2S+20.
3S-10 = 2S+20.
S = 30 <----- Son's Age.
Again using (i).
F = 3(30)-20.
F = 70.
So Ratio is 70:30 ----> 7:3.
10 Years Ago:
F-10 = 3(S-10).
F = 3S-20 ------ (i).
10 year hence:
F+10 = 2(S+10) ------ (ii).
Replace (i) in (ii).
3S-20+10 = 2S+20.
3S-10 = 2S+20.
S = 30 <----- Son's Age.
Again using (i).
F = 3(30)-20.
F = 70.
So Ratio is 70:30 ----> 7:3.
Shreyas said:
1 decade ago
Let f be the father's age and x be the son's age.
10 years ago.
f-10 = 3(x-10)
f = 3x-30+10
f = 3x-20 -----------(1)
10 years hence
f+10 = 2(x+10)
f = 2x+20-10
f = 2x+10 -----------------(2)
From 1 & 2
2x+10 = 3x-20
x = 30;
f=2*30 +10 ----from 2
f= 70;
Ratio is 7:3
10 years ago.
f-10 = 3(x-10)
f = 3x-30+10
f = 3x-20 -----------(1)
10 years hence
f+10 = 2(x+10)
f = 2x+20-10
f = 2x+10 -----------------(2)
From 1 & 2
2x+10 = 3x-20
x = 30;
f=2*30 +10 ----from 2
f= 70;
Ratio is 7:3
Vaishnavi said:
9 years ago
Express the following linear equation in two variables by talking present ages of his father and son as x and y respectively.
Age of father 5 years ago was two years more than 7 times the age of his son at that time.
Can anyone help me?
Age of father 5 years ago was two years more than 7 times the age of his son at that time.
Can anyone help me?
Jamzeer Narayan Mahato said:
9 years ago
Please solve this.
I am Jamzeer Narayan Mahato.
The present age of the father is four times the age of his son, when the son will be as old as his father now, the sum of their ages will be 99, find their present ages.
Thank in advance.
I am Jamzeer Narayan Mahato.
The present age of the father is four times the age of his son, when the son will be as old as his father now, the sum of their ages will be 99, find their present ages.
Thank in advance.
Deepika and kavipriya said:
2 months ago
The son age is x.
10 years ago, father is age was 3x-10.
After 10 years, father's age is 2x+10.
then,
3x-10 = 2x + 10.
x = 20.
The required ratio is = (3x+10):(x+10).
= 70:30,
= 7:3.
10 years ago, father is age was 3x-10.
After 10 years, father's age is 2x+10.
then,
3x-10 = 2x + 10.
x = 20.
The required ratio is = (3x+10):(x+10).
= 70:30,
= 7:3.
(9)
VIKAS KOHLI said:
10 years ago
Let's present ages of father and son will be x and y.
Before 10 yearss, it will be (x - 10) = 3(y - 10).
Ten years hence , the equation will be x + 10 = 2(y + 10).
Solve these two equations, we get x = 70 years and y =30 years.
Before 10 yearss, it will be (x - 10) = 3(y - 10).
Ten years hence , the equation will be x + 10 = 2(y + 10).
Solve these two equations, we get x = 70 years and y =30 years.
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)
Devendra said:
1 decade ago
All the trick are good but Malic trick is so, esy but one confusion here X=20 mens ago(back 10 year) &Hence(after 10yer) so.. 10+10 X=20.............
(3x+10):(x+10)=7:3........... Just put the value of X=20......
(3x+10):(x+10)=7:3........... Just put the value of X=20......
Mihir said:
1 decade ago
Can anybody tell the answer to this question?
In 1996, Raju age was equal to the numbers formed by the last two digits of his birth year. This was same for his grandfather also. Find the difference between their ages.
In 1996, Raju age was equal to the numbers formed by the last two digits of his birth year. This was same for his grandfather also. Find the difference between their ages.
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