There are 60 students x 2/3 = <<60*2/3=40>>40 students who have a $6 daily allowance.
While there are 60 students - 40 students = <<60-40=20>>20 students who have a $4 daily allowance.
The sum of the allowances of the 40 students who received $6 daily is 40 students x $6/day = $<<40*6=240>>240.
The sum of the allowances of the 20 students who received $4 daily is 20 students x $4/day = $<<20*4=80>>80.
The total daily amount of money of those 60 students is $240 + $80 = $<<240+80=320>>320.
#### 320