All math genius help ?

What are the exclude value of mn+3m

The value of the expression 16-^3/4 8 1/8 -6 6 1/40 1/64

Mike wants to make meatloaf. his recipe uses a total of 8 pounds of meat. if he uses a 3 to 1 ratio of beef to pork, how much pork will he use? enter your answer as a mixed number in simplest terms.