The sides of a cube measures 6.5cm. If the surface area of the cube is the same as a ball, what is the radius of the ball? Round to the nearest whole number. Choices.
A) 9  B) 7  C) 4  D) 8  E) 6
First calculate the surface area of the cube. The cube is made of 6 squares with the sides measuring 6.5cm each. The surface area of 1 side of the cube is 42.25cm. Multiply the surface area of the 1 side by 6 will give you the cube's total surface area. The cubes surface area is 253.5cm. Now we know that the surface area of the ball is 253.5cm. To find out the surface area of a sphere you need to square the radius, then multiply by Pi, and multiply by the number 4. Going backwards to find the radius - you will need to dived the surface area by 4. Then divide by Pi. Then determine the square root of the answer. The radius is 4.460. Rounding to the nearest whole number the radius is 4. The correct answer is (4).
<result>C</result>
The sides of a cube measures 6.5cm. If the surface area of the cube is the same as a ball, what is the radius of the ball? Round to the nearest whole number.