Question

the age of the father is equal to the sum of the age of his 4 childern.after 20 years ,sum of the age of the childern will be twice the age of the father,what is the age of the father

Answer 1

Answer:

40

age of the father is 40

Step-by-step explanation:

2x+40=x+80

or x=40

Answer 2

Let sum of Age of 4 children=(a+b+c+d) years

Father age is sum of His 4 children=(a+b+c+d) years

After 20 years

Age of all children will be increase by 20 years.

Now Sum of All Children age.

(a+20+b+20+c+20+d+20)

Father age will be=(a+b+c+d)+20 years

children age will be Twice the sum of age of Father after 20 years

(a+20+b+20+c+20+d+20)=2(a+b+c+d+20)

a+20+b+20+c+20+d+20=2(a+b+c+d+20)

a+b+c+d+80=2a+2b+2c+2d+40

a+b+c+d-(2a+2b+2c+2d)=40-80

a+b+c+d-2a-2b-2c-2d=-40

-a-b-c-d=-40

-(a+b+c+d)=-40 [(-)×(-)=+]

a+b+c+d=40

Age of Father=(a+b+c+d)=40 years

Father=40 years