First, let's solve the inner parentheses first:

72(20,74:6,8-7,6:19)
= 72(20.74 / 6.8 - 7.6 / 19)
= 72(3.04411765 - 0.4)
= 722.64411765
= 190.1029416

Now, let's plug this value back into the outer parentheses:

(25,8-3,190.1029416)0.5
= (22.8 - 95.05168)0.5
= (-72.25168)*0.5
= -36.12584

Therefore, the final answer is -36.12584.