MeTest_OS2

Question

Doubt1: Is question properly framed?

Doubt2: Assuming Doubt1 says yes, Say there are 5 processes $P_1,P_2,P_3,P_4,P_5$ and say all have total execution time of 10 units. Now out of this 10 units, 3 units will be for I/O of each process, but since I/O can proceed in parallel, So, say all processes arrived at t=0, then only first 3 units of time CPU will be idle and hence CPU Utilisation is (35/38)*100.Is this correct?

Comments

even my answer was 35/38 * 100 because only 3ms cpu will be idle out of the 38ms;

i dont think their answer is correct because 1-0.3⁵ does not makes any sense either it should be (1-0.3)⁵

but we will be considering the 5 processes together so i guess it should be 35/38 * 100 %