An hourglass, composed of two identical cones, is 12 cm tall. The radius of each cone is 3 cm. If you want to fill the bottom half of the hourglass full of salt, how much salt will you need? Explain the method you would use to find the amount of salt.

Answer 1

bottom half is a cone. r=3, h=6

v = 1/2 pi r^2 h

Now just plug in the numbers

Answer 2

oops. 1/3 pi r^2 h

Answer 3

37.68 cm^3