VMLS Question

in problem 1.1
sir how we solved this question .

i approached the method like that we have 8 hrs in question, i converted at in second = 86060 = 28800 we already know that they are interval of 10 sec so we have 2880 frequency to do that on average its taking 0.9 sec from julia terminal. we have to find time for each day so its being a 2592 . is this right approach to solve this problem.