Sum of the ages of a boy and his father is 70 years. Before 20 years Father's age was 9 times the ag

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23 Dec 2016 Ages

Sum of the ages of a boy and his father is 70 years. Before 20 years Father's age was 9 times the age of the boy. What was the age of father in years at the time of birth of the child?

OPtion

1) 23
2) 24
3) 26
4) 27
5) 29
6) 33
7) 34
8) 36
9) 47
10)48

Solution

Let the present age of father and son be x and y respectively
According to the given condition
x+y = 70 ---- (i)
before 20 years
(x-20) = 9(y-20)
Replacing value of x from equation (i)
so 70-y-20 = 9(y-20)
=> 50-y = 9y-180
=> 10y = 230
=> y = 23 and x = 47
so at the time of birth of child, age of father = 47-23 = 24 years

Option 2)

Correct Option: 2 Best Solution (19)

PRABHAT KUMAR   8 years AGO

father +son=70(current age)
20 years ago,
father:son=9x:x
so 10x+2*20=70
x= 3
so 20years ago
father 27
son. 3
now age of father at the time of son birth =27-3=24
option 2
mate!!!!!!

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ARYASREE   8 years AGO

sum of ages of father and son=70 years
before 20 years,age of son be x,
then age of father is 9 times the age of son=9x
before 20 years sum age will be =70-(20+20)=30years.
solving 9x+x=30
x=3
20 years ago, son's age=3years
fathers's age=27 years.
at the time of birth age of father=27-3=24years.

Like? Yes (1) | No   

Mukund Manohar   8 years AGO

Let the present age of father and son be x and y respectively
(x-20) = 9(y-20)
70-y-20 = 9y-180
y=23 and x=47
Required age = 47-23 = 24 years

Like? Yes (1) | No   

Arshi   8 years AGO

let the age of son is =x
father age is=70-x
before 20 year
70-x-20=9(x-20)
x=23
father =70-23=47
before 20 year
father=47-20=27
child=23-20=3
father age at the time of birth of a child=27-3=24year
Ans-24year

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nimesh tiwari   8 years AGO

let age of son -x and father-y
sum if present age [x+y=70]
ATQ.. 20 yrs back :> [ {

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REVATHI   8 years AGO

B+F=70.
F=9B-160
B=23.
F=47.
FATHER AGE AT TIME OF BOY BIRTH=47-23=24

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Divya Vasudevan   8 years AGO

Let father's age be x years.
X-20=9((70-x)-20)
On solving x=47
At present Father's age=47
Son's age=23 years
So father's age at time of Son's birth=24 years

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Sandip Das   8 years AGO

boy = b
father =f
b+f =70
before 20 years
b = b-20
f = 9 * (b-20)
so
b-20+9b-180 = 70-40
b = 23
so
b= 23-20
= 3
f = 9*3 =27
when child was birth the father age was f= 27-3= 24 (option 2)

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Karan   8 years AGO

Sum of ages 20 years ag0 = 70-40=30 years
Age of father 20 yrs ago= 27 yrs
Age of son 20 years ago=3 yrs
Age of father at the time of birth of son = 27-3=24 years

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Vivek   8 years AGO

Let X be the age of Son
Let Y be the age of Father
X + Y = 70
23 + 47 = 70
Let x be the age of Son before 20 years,
Let y be the age of Father before 20 years,
(y = 9 * x)
(23 - 20) = 3
(47 - 20) = 27
3 * 9 = 27
At the birth of his son, (before 23 years)
age of the Father = 47 - 23 = 24

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Chavan Shweta   8 years AGO

B+F=70
(F-20)=9(B-20)
solving these equations we get,
B=23 and F=47
at the time of birth of son the father,s age will be=47-23=24

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Parveen Soni   8 years AGO

let a be father's age and b be son age at current time
so we have
a+b=70 and a-20(9(b-20) -->
a=47 and b=23
so when son was born father age was 47-23=24 years.

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Rumitra Lahiri   8 years AGO

let age of son is x and father is y
x+y=70
9(x-20)=y-20
by solving x& y we get
x=23
y=47
so present age of the boy 23& father47
at the time of birth age of father was=(47-23)=24

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JENSI KARUNYA.S   8 years AGO

let the ages of boy and father be B and F respectively
F+B=70---->(1)
(F-20)=9(B-20)
F-9B=-160------->(2)
solve the equations (1) and (2),
the present age of the father,F=47
the present age of the boy,B=23
at the time of boy's birth, father's age=47-23=24.
so, the option (2) 24 is the correct answer.

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Devendra Marghade   8 years AGO

Let the present ages of father=x and his son=y years, then
x+y= 70 ---(i) and
(x-20) = 9(y-20) or x-9y= -160 ---(ii)
On solving (i) & (ii), x=47, y=23
So father's age at the time of birth of a son=47-23=24 years

Option 2)

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swagat   8 years AGO

even the sum of ages were 70 now. 20 years ago it was 30inthat 9 parts father and one part for son ..so father age at the time of boy born is 24years....

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Pragati Rode   8 years AGO

let age of boy is x
so father's age = 70-x

before 20 years ,
father's age = 9 * age of boy
70 - (x-20)=9*(x-20)
70 - x+ 20 = 9x -180
10x=180 +50
10x=230
x=23
age of boy is 23 and father's age = 70 -x = 70 - 23=47
so At the time of birth of the child ,the age of father was 47 - 23 = 24 years
so option is 2

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perico palote   8 years AGO

b+f=70
f-20=9(b-20)

then f=47, b=23
and f(at boy's birth)=f-b=24

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Lakshmi Narayanan.k   8 years AGO

B+F=70
F-20=9[B-20]
Solving 2 eqn we get
B=23;F=47
If B=0;then F=24. opt 2

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