A bacterial culture was infected with two strains of a virus. One strain was minute (m), turbid (tu) and acriflavin-resistant (a), while the other one was wildtype for all the three genes. The resulting 10000 plaques were distributed among the genotypes listed below.

m tu a = 4000
+ + +   = 3900
m + +  =   800
+ tu a  =   720
+ tu +  =   200
m + a  =   200
+ + a   =      80
m tu + =    100

Identify the order of genes.