Answer: There are 770 more appliances that can be produced.
Step-by-step explanation:
Since we have given that
[tex]f(x)=280x[/tex]
Here, x is the number of hours.
Number of appliances per hour = 280
If the number of hours = 7
So, [tex]f(7)=280\times 7=1960[/tex]
If the number of hours = [tex]4\dfrac{1}{4}=\dfrac{17}{4}[/tex]
So, [tex]f(\dfrac{17}{4})=280\times \dfrac{17}{4}=70\times 17=1190[/tex]
Number of more appliances that can be produced is given by
[tex]1960-1190\\\\=770[/tex]
Hence, there are 770 more appliances that can be produced.