Amy and Belinda each roll a sheet of 6-inch by 8-inch paper to form a cylindrical tube. Amy tapes the two 8-inch sides together without overlap. Belinda tapes the two 6-inch sides together without overlap. What is times the positive difference of the volumes of the two tubes?
8 inch paper will be x
6 inch paper will be y
The height for x is 8, and the circumference is 6
The height for y is 6, and the circumference is 8
Then just multiply whatever number you put in that blank space and there you go!
Radius of Amy's cylinder = 6/(2pi ) = 3/pi
Height of Amy's cylinder = 8
Radius of Belinda's cylinder = 8/(2pi) = 4/pi
Height of Belinda's cylinder = 6
Volume of Amy's cylinder = pi ( 3/pi)^2 ( 8) = 72/pi
Volume of Belinda's cylinder = pi ( 4/pi)^2 ( 6) 96/pi
Positve difference between the volumes = (96 - 72) / pi = 24 / pi