It is given in the question that
It takes h hours to paint a rectangular wall that is x feet wide and y feet.
Area of the rectangular wall is the product of length and width that is
[tex] Area = xy \ feet^2 [/tex]
And for an area of xy square feet, it takes h hour.
So for 1 square feet, it will take
[tex] = \frac{h}{xy} hours [/tex]
And for the number of minutes, we have to multiply it by 60, that is
[tex]=\frac{60h}{xy} minutes[/tex]
