The following table shows the number of employees and their median age in eight companies located in a district.

It is known that the age of all employees are integers. It is known that the age of every employee in A is strictly less than the age of every employee in B, the age of every employee in B is strictly less than the age of every employee in C, ..., the age of every employee in G is strictly less than the age of every employee in H.

The median age of employees across the eight companies is:

The total number of employees across all the 8 companies is 32+28+43+39+35+29+23+16=245.

The age of the $$\left(\frac{245}{2}+1\right)^{th\ }ie\ 123^{rd}$$ employee will be the median of the data set, when they all are arranged in ascending order. 

The total number of employees in companies A, B, and C together is 103, and the total number of employees in A, B, C and D is 142.

This means the 123rd employee should be in company D; and then arranged in ascending order he would be the (123-103)=20th employee in the company.

Now, for company D , the total number of employees is 39, which means the median age of the company will be the age of the $$\left(\frac{39+1}{2}\right)^{th\ }ie\ 20^{th}$$ employee, which is given to be 45.

So the age of the 123rd employee, when all the companies are considered together, is 45, which will be the required median.