we know that
The recipe says [tex]2\frac{1}{4}[/tex] cups of flour are needed for each batch
so
by proportion
Find how many cups of flour will Marcus use to make [tex]3[/tex] batches of cookies
Convert mixed number to an improper fraction
[tex]2\frac{1}{4}=2.25[/tex]
[tex]\frac{2.25}{1} \frac{cups}{batch} =\frac{x}{3} \frac{cups}{batch} \\ \\x=2.25*3\\ \\x=6.75\ cups[/tex]
Convert to a mixed number
[tex]6.75\ cups=6+0.75=6+\frac{3}{4}=6\frac{3}{4}\ cups[/tex]
therefore
the answer is
[tex]6\frac{3}{4}\ cups[/tex]
