Given these facts, determine how many cans of paint you would need to buy to paint 2 walls.

1st wall: 20 ft. x 8ft.
2nd wall: 40ft. x 8ft.
1 can will cover 200 square feet of wall.


  1. You will need 3 cans of paint to cover the two walls

    How many cans of paint will you need?

    We know that 1 can will cover 200 square feet of wall.
    And here we have 2 walls, let’s find the total area of these walls.
    wall 1 is 20ft by 8ft, then its area is:
    A = 20ft*8ft = 160ft^2
    wall 2 is 40t by 8 ft, then its area is:
    A’  = 40ft*8ft = 320ft^2
    The total area is:
    160ft^2 +  320ft^2 = 480ft^2
    The number of cans of paint needed is given by the quotient between the total area and the area that each can cover.
    N = 480ft^2/200ft^2 = 2.4
    But we can’t have a 0.4 of a can, so we should round to the next whole number, which is 3.
    If you want to learn more about area:


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