Answer: 
$60 million 
Explanation: 
The computation of the value of operations after the repurchase is shown below:- 
Total corporate value = Value of operation + marketable securities 
(5 × $15 million) = Value of operation + $15 million
$75 million = Value of operation + $15 million
Value of operation = $75 million - $15 million
= $60 million 
We simply applied the above formula so that the firm's value of operations after the repurchase could come