Cost Price for oil change =$27
Charge for the customers =$40
Markup cost = Difference between selling price and cost price =$40-$27=$13
To find the percent of markup, divide the markup cost by the cost price and multiply it by 100.
Markup percent = (13/27)*100
=48.15%
X<=-5 is what it looks like to me
The vol. of a cube of side length s is V=s^3.
So, if the side length is 5a+4b, then the volume of the cube is
V(a, b) = (5a+4b)^3. This could, of course, be expanded, using the binomial theorem, but there's no point in doing so.