A bakery has bought 15 pounds of flour. They are going to use it to make bread and donuts. A loaf of bread requires two pounds of flour, and a dozen
donuts requires one pound of flour. It takes bakers 5 minutes to make a
loaf of bread, and 3 minutes to make a dozen donuts. Their profit will be
$3.00 on a loaf of bread, and $1.50 on a dozen donuts.
Determine the variables for the above situation.