Answer:
Mark will use 1.25 pounds of pork.
Step-by-step explanation:
Let b represent the number of pounds of pork and p represent the number of pounds of beef. Since the ratio of beef to pork is 3 to 1, we have b/p = 3/1, which then becomes b = 3p. From this:
[tex]3p + p = 7[/tex]
[tex]4p = 7[/tex]
[tex]p = 1.75[/tex]
[tex]b = 3 \times 1.75 = 5.25[/tex]