Step 1: Assume the present age of the son.
Let the present age of the son be \( x \) years.
Then, the present age of the father will be \( x + 10 \) years.
Step 2: Write the ages after 10 years.
After 10 years, the son’s age will be \( x + 10 \) years.
After 10 years, the father’s age will be \( x + 20 \) years.
Step 3: Form the equation using the given condition.
According to the question, after 10 years, the father’s age will be 1.5 times the son’s age.
\[
x + 20 = 1.5(x + 10)
\]
Step 4: Solve the equation.
\[
x + 20 = 1.5x + 15
\]
\[
20 - 15 = 1.5x - x
\]
\[
5 = 0.5x
\]
\[
x = 10
\]
Step 5: Find the present age of the father.
Present age of the father = \( x + 10 = 10 + 10 = 20 \) years.
Step 6: Conclusion.
The present age of the father is 20 years.