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 6 of 8.
Mickey said:
1 decade ago
Present ages be
father = x
son = y
10 years ago,
father = x-10
son = y-10
a/q
(x-10)= 3(y-10)..........1
10 years hence,
father = x+10
son = y+10
a/q
(x+10)= 2(y+10).......2
We get x=70, y=30.
father = x
son = y
10 years ago,
father = x-10
son = y-10
a/q
(x-10)= 3(y-10)..........1
10 years hence,
father = x+10
son = y+10
a/q
(x+10)= 2(y+10).......2
We get x=70, y=30.
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......
Vic said:
1 decade ago
TO SOLVE BOTH THE EQUATIONS
3X+10=2X-10 WHERE X=20
SO PUT THE X VALUE IN PLACES OF X
WILL PRODUCE THE RATIO
70:30 i.e=7:3
3X+10=2X-10 WHERE X=20
SO PUT THE X VALUE IN PLACES OF X
WILL PRODUCE THE RATIO
70:30 i.e=7:3
Anu said:
1 decade ago
Can anybody tell me how to find the ratio?
Narayan said:
1 decade ago
Some time it good to solve question without any quick formula.
Thanks Mickey.
Thanks Mickey.
Mani said:
1 decade ago
Thanks to all. Now I got some idea.
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
Srk said:
1 decade ago
Only 7:3 is viable when plugged in
G Naresh said:
1 decade ago
Let the ages of father and son 10 years ago be 3x and x years respectively.
Then, (3x + 10) + 10 = 2[ (x + 10) + 10].
How it is possible for adding 10 two times?
Then, (3x + 10) + 10 = 2[ (x + 10) + 10].
How it is possible for adding 10 two times?
Rohit said:
1 decade ago
(3x + 10) + 10 = 2[ (x + 10) + 10]. Why we multiply right hand side of eq by 2 instead of left. As father age is twice so why we multiply son's age eq. Please explain?
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers