Answer:
[tex]0.2\%\ people\ had\ a\ mild\ allergic\ reaction.[/tex]
Step-by-step explanation:
[tex]Total\ number\ of\ people=4000\\\\People\ had\ allergic\ reaction=8\\\\In\ 4000\ people\ allergic\ reaction=8\\\\For\ 1\ people\ ratio\ will\ =\frac{8}{4000}\\\\In\ 100\ people\ allergic\ reaction=\frac{8}{4000}\times 100=\frac{1}{5}=0.2\%\\\\Hence\ 0.2\%\ people\ had\ a\ mild\ allergic\ reaction.[/tex]