Hey, here is your answer....

let x = the age of the father today.
let w = the sum of the ages of the children today. 

since the age of the father today is 2 times the sum of the age of the children today, the formula for that will be: 

x = 2w 

in 20 years, the age of the father will be x + 20.
in 20 years, the sum of the age of the children will be w + 40.
this is because each child has aged 20 years, so the sum of the years the 2 children have aged is 40. 

the formula for the age of the father the the sum of the ages of the children in 20 years becomes: 

x + 20 = w + 40 

you have 2 equations that need to be solved simultaneously. 

they are: 

x = 2w
x + 20 = w + 40 

because x = 2w from the first equation, replace x with 2w in the second equation to get: 

2w + 20 = w + 40 

solve for w to get: 

w = 20 

since x = 2w, this means that x = 40 

the age of the father today is 40.

I hope u will understand.. Thank u

Problem:
The age of the father is twice the sum of the ages of his two children. After 20 years, his age will be equal to the sum of the ages of his children. Find the age of the father.

Given Information:
Let's assume the age of the father is F years, and the ages of the two children are C1 and C2 years respectively.

1. The father's age is twice the sum of his children's ages: F = 2(C1 + C2).
2. After 20 years, the father's age will be equal to the sum of his children's ages: F + 20 = (C1 + 20) + (C2 + 20).

Solution:

To solve this problem, we can use the given information and solve the equations simultaneously.

1. The father's age is twice the sum of his children's ages: F = 2(C1 + C2).
2. After 20 years, the father's age will be equal to the sum of his children's ages: F + 20 = (C1 + 20) + (C2 + 20).

Let's simplify the second equation:
F + 20 = C1 + C2 + 40

Now, substitute the value of F from the first equation into the second equation:
2(C1 + C2) + 20 = C1 + C2 + 40

Simplify the equation further:
2C1 + 2C2 + 20 = C1 + C2 + 40

Combine like terms:
C1 + C2 + 20 = 40

Subtract 20 from both sides of the equation:
C1 + C2 = 20

Now we have two equations:
F = 2(C1 + C2)
C1 + C2 = 20

Solve the second equation for C1:
C1 = 20 - C2

Substitute the value of C1 in the first equation:
F = 2((20 - C2) + C2)

Simplify the equation:
F = 2(20 - C2 + C2)
F = 2(20)
F = 40

Therefore, the age of the father is 40 years.