posted by Reeces .
1.Which solid has one base that is a triangle and three lateral surfaces that are triangles?
2.A solid with two parallel and congruent bases cannot be which of the following:
3.A cone has a radius of 15 cm and a volume of 540 cm^3. Find the volume of a similar cone with a radius of 10 cm.
How do I solve 3?
#1 #2 are ok
the volumes are in the cube of the linear ratio. So, v' = (10/15)^3 v = 8/27 v = 160
This is due to the fact that each dimension scales the same way. In the case of the sphere, replace r by (2/3)r in the formula. Then you get
v = 4π/3 r^3
v' = 4π/3 (2/3 r)^3
= 4π/3 (2/3)^3 r^3
= (2/3)^3 v
Are you sure number 2 is good, i thought it was sphere