[SunilNagpal]

One hundred E coli cells are infected by a single lambda phage particle. the ratio of the number of phage particles committing to lysogeny to those committing to lysis is 4:1. Assuming that the average burst size is 80 , the number of free phage particles released after on round of infection is?

I am sorry if I'm missing some crucial information regarding lytic and lysogenic cycles (which should have been used for approaching this question), I am rather assuming it as a simplistic question....

Given the 4:1 for lysogenic : lytic phages, it is clear than 20 would be lytic phages. 

Now each E.coli will burst once 80 particles have been accumulated. 

So total free particles should be 20x80 = 1600