Aptitude - Problems on Ages - Discussion
Discussion Forum : Problems on Ages - General Questions (Q.No. 8)
8.
The sum of the present ages of a father and his son is 60 years. Six years ago, father's age was five times the age of the son. After 6 years, son's age will be:
Answer: Option
Explanation:
Let the present ages of son and father be x and (60 -x) years respectively.
Then, (60 - x) - 6 = 5(x - 6)
54 - x = 5x - 30
6x = 84
x = 14.
Son's age after 6 years = (x+ 6) = 20 years..
Discussion:
71 comments Page 6 of 8.
Pandi said:
1 decade ago
Now son age x and father age is y
then
x+y=60---->1
six years before son=x-6, father=5(x-6)
so
y-6=5(x-6)
y-6=5x-30
5x-y=24--->2
solve 1 and
get x=14
x is present age
after six years x+6=20
then
x+y=60---->1
six years before son=x-6, father=5(x-6)
so
y-6=5(x-6)
y-6=5x-30
5x-y=24--->2
solve 1 and
get x=14
x is present age
after six years x+6=20
Chandana said:
1 decade ago
I think so...
it's after 6 years,
in eqn x-6=5y u didnt reduced son's age to 6years(after 6years)
x-6=5(y-6)
then u get the answer..
x-6=5y-30
x=5y-24;
5y-24+y=60
6y=84
y=14
hence present age of son=y+6=20
it's after 6 years,
in eqn x-6=5y u didnt reduced son's age to 6years(after 6years)
x-6=5(y-6)
then u get the answer..
x-6=5y-30
x=5y-24;
5y-24+y=60
6y=84
y=14
hence present age of son=y+6=20
Kauthik said:
1 decade ago
Father's age = x ; son's age = y
x+y = 60; x-6 = 5y; y+6 = ?
x = 5y+6
5y+6+y = 60
6y = 54
y = 9
Hence present age of son = y+6= 15.
I got answer like this. what's wrong in this method.
x+y = 60; x-6 = 5y; y+6 = ?
x = 5y+6
5y+6+y = 60
6y = 54
y = 9
Hence present age of son = y+6= 15.
I got answer like this. what's wrong in this method.
Selvi.k said:
1 decade ago
We will solve this problem by solving the two equation
Consider son's age=Y, Fathers age=X.
Let X+Y=60. (1)
6 years ago means
Son's age=X-6, Fathers age=Y-6.
So the equations changed as per the condition
5Y-6=X-6.
We get,
X-5Y=-24. (2).
Solve (1) , (2).
We get y=14, x=46.
After 6 years the son's age=14+6=20.
Consider son's age=Y, Fathers age=X.
Let X+Y=60. (1)
6 years ago means
Son's age=X-6, Fathers age=Y-6.
So the equations changed as per the condition
5Y-6=X-6.
We get,
X-5Y=-24. (2).
Solve (1) , (2).
We get y=14, x=46.
After 6 years the son's age=14+6=20.
Venkatesh said:
1 decade ago
A+B=60,--->1
6 yrs ago , (A-6)=(B-6)*5[bcz Six years ago, father's age was five times the age of the son]
A-6=5B-30,
A=5B-24, ----->2
By simplifying 1 and 2 we will get B=16.
Aft 6 yrs B+6=20.
6 yrs ago , (A-6)=(B-6)*5[bcz Six years ago, father's age was five times the age of the son]
A-6=5B-30,
A=5B-24, ----->2
By simplifying 1 and 2 we will get B=16.
Aft 6 yrs B+6=20.
Yakesh said:
1 decade ago
Before(6 years back): 5x, x
Present:5x+6, x+6
After 6 years:5x+12,x+12
and 5x+6+x+6=60
x=8
after 6 years = x+12 = 8+12 = 20.
Present:5x+6, x+6
After 6 years:5x+12,x+12
and 5x+6+x+6=60
x=8
after 6 years = x+12 = 8+12 = 20.
Appatakar said:
1 decade ago
Awesome pallavi thanks.
Manoj verma said:
1 decade ago
Suppose son's age=x father's age=y x+y=60 y-6=5(x-6) 60-x-6=5x-30 6x=84 x=14 after 6 years son's age=20
Priya said:
1 decade ago
Let s be son and f be father.
s+f=60
this was 6 years ago there fore
(s+f)-6=60-6 . . .here f=5s therfore substut
s+5s-6=54 . . .6s=60
therefor s=10
aftr 6 years
s=16
Please tell wats wrong with my logic.
s+f=60
this was 6 years ago there fore
(s+f)-6=60-6 . . .here f=5s therfore substut
s+5s-6=54 . . .6s=60
therefor s=10
aftr 6 years
s=16
Please tell wats wrong with my logic.
Rajinder said:
1 decade ago
The sum of son and father's age can be written as
S+F=60 ----------(1)
before 6 years ago
5(S-6)=F-6
5S-30=F-6
5S-F=-6+30
5S-F=24 ----------(2)
ADDING (1) and (2),weget
6S=84
S=84/6=14
put s=14 in ist weget
F=46
Hence after 6 years Son;s age will be 14+6=20 years.
S+F=60 ----------(1)
before 6 years ago
5(S-6)=F-6
5S-30=F-6
5S-F=-6+30
5S-F=24 ----------(2)
ADDING (1) and (2),weget
6S=84
S=84/6=14
put s=14 in ist weget
F=46
Hence after 6 years Son;s age will be 14+6=20 years.
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