Ludwig earns a total of $10 x 4 = $<<10*4=40>>40 from Monday to Thursday.
He earns $10/2= $<<10/2=5>>5 per day on Friday, Saturday, and Sunday.
So, his total salary for Friday, Saturday, Sunday is $5 x 3 = $<<5*3=15>>15.
Therefore, his total weekly salary is $40 + $15 = $<<40+15=55>>55.
#### 55