Question

A tank in the shape of a cone has a diameter of 8 feet and a height of 10 feet.when there is water in the tank, th water is in the shape of a cone too. find the radius of the cone of water when the water is 2 feet high. Explain how you would solve it.

Answer 1

first, imagine the front view of the cone,, it should look like an inverted triangle,, then draw the content (the water - horizontal line),, note that if you draw a vertical line bisecting the inverted triangle, you actually form a right triangle,,

since you bisected it, get the radius: r= d/2 = 8/2 = 4 feet
then draw another horizontal line for which height is 2 feet,,

recall similar triangles,, you just have to do ration and proportion of the base and height,, therefore:
let x = radius when height is 2 feet
4/x=10/2
x= 4/5 or 0.8 feet

so there,, =)