A rectangular cube has sides measuring 15 inches long by 12 inches wide by 2 inches high. If the surface area of the rectangle is the same as a cube, what do the sides/walls of the cube measure? Round to the nearest whole number. Choose the correct choice from the following choices
A) 7 B) 5 C) 9 D) 6 E) 4
First calculate the surface area of the rectangle by multiplying the length and width of the rectangle together, then multiply by 2 to get both sides of the rectangle. This calculates to 360 inches. Find the surface area of the sides of the rectangular cube. Multiply the height by the length of the rectangle. Multiply the answer by 2 (for the 2 sides on the rectangular cube). This calculates to 60 inches. Then multiply the width of the rectangle by the height. Multiply the answer by 2 (for the 2 sides on the rectangular cube). This calculates to 48 inches. Add the totals together to get the rectangular cube surface area of 468 inches. Since a square cube has 6 sides - divide the surface area by 6. This calculates to 78 inches as the surface area of each side of the cube. The square root of 78 is 8.831. Rounding to the nearest whole number that makes each side of the cube measuring 9 inches. The correct answer is (9).
<result>C</result>
A rectangular cube has sides measuring 15 inches long by 12 inches wide by 2 inches high. If the surface area of the rectangle is the same as a cube, what do the sides/walls of the cube measure? Round to the nearest whole number.