0:00:00.000,0:00:06.000
One way of solving this is to find out which terms appear in several places--

0:00:06.000,0:00:13.000
for instance, this one--the number of persons taken from the susceptible to the exposed compartment

0:00:13.000,0:00:18.000
and then the number of persons taken from the exposed to the infectious compartment,

0:00:18.000,0:00:23.000
and the number of persons taken from the infectious to the recovered compartment.

0:00:23.000,0:00:27.000
If you write it like that, it's easier to read and you can immediately see

0:00:27.000,0:00:29.000
that the total number is conserved.

0:00:29.000,0:00:36.000
The number of persons we lose here we gain here, the number of persons we lose here we gain here,

0:00:36.000,0:00:39.000
and the number of persons we lose here is gain here.

0:00:39.000,0:00:45.000
So up to very tiny round off errors of the total number and result you'll see that the infection

0:00:45.000,0:00:47.000
takes quite some time to evolve.

0:00:47.000,0:00:52.000
The maximum of the exposed compartment comes first and then comes

0:00:52.000,0:00:57.000
the maximum of the infectious compartment, and as we go, you'll see that the number of

0:00:57.000,0:00:59.000
susceptible persons shrinks drastically

0:00:59.000,9:59:59.000
and the number of recovered persons grows by the same amount.