16.7 cm

Question

5 cm
COURSE TOOLS
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8.9 cm
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LESSON FEEDBACK
15.9 cm
A wooden door stopper needs to be covered with stickers to match the door for a directing contest. If one package of stickers covers a surface area of 75 square centimeters, how many packages of stickers need to be purchased? (Find the closest number to the surface area of the door stopper. Stickers may only be purchase in whole packs.)
(1 point)
• You will need 6 packages of stickers.
• You will need 5.5 packages of stickers.
• You will need 414.14 cm? packages of stickers.
• You will need 7 packages of stickers.

Answer 1

To find the surface area of the door stopper, we need to calculate the area of all the sides.

The front and back sides each have an area of 16.7 cm x 5 cm = 83.5 square cm.
The top and bottom sides each have an area of 8.9 cm x 5 cm = 44.5 square cm.
The two side walls each have an area of 15.9 cm x 5 cm = 79.5 square cm.

Adding all the areas together, we get a total surface area of 83.5 + 83.5 + 44.5 + 44.5 + 79.5 + 79.5 = 415.5 square cm.

Since one package covers 75 square cm, we need to divide the total surface area by the area covered by one package:
415.5 square cm / 75 square cm = 5 packages of stickers.

Therefore, you will need 5 packages of stickers to cover the door stopper. The closest answer option is:
• You will need 5.5 packages of stickers.