Question 1133999
I first divided 40 m^2 by 8 m^2 to determine it would take 5 hours to paint with the roller.  Adding on 1/2 hour for clean up, 5.5 was multiplied by 11 to determine it would cost $60.50 to have the painter paint using a roller.

40 m^2 divided by 20 m^2 gives 2, which means it would take 2 hours to paint with the spray gun.  2 plus the 1 hour cleanup gives 3 hours, times $11 an hour is $33.  The 3 hours is also multiplied by $5 per hour for the rental of the gun.  The $15 is added onto the $33 for a total of $48.

Finally, $48 is subtracted from $60.50 to determine the savings.

*[illustration paint]