EOC Strategy - GEOMETRYFormulas

STRATEGY #1CIRCLE FORMULAS & UNDERLINE VARIABLES

If there is a formula:

-circle formula -label info -plug in

You will need to memorize: Volume of a cylinder V = r2h

Pay attention to radius & diameter & remember: Diameter = 2 times radius Radius = ½ diameter

Example G3.1

The volume, V, of a sphere can be found using the equation ,

V = r3 given the radius, r, of the sphere. What is the approximate radius of a sphere with a volume of 178 cubic centimeters?

Other things to think about

Sometimes you will need to take another step after you find the missing part in the problem.

Example G3.2

Bubba has a cylindrical bottle that is 6 inches tall and has a 2 inch radius.

How much taller must the bottle be in order to hold about twice as much water?

CHECK IT G3.3

A cylindrical can is 10 cm tall and has a diameter of 8.5 cm. What is the approximate volume of the can?

CHECK IT G3.4Jessica was building a cone for her rocket in science class. The volume of the cone was 42 cubic inches. The radius of the cone was 2 inches. About what height was the cone? (Use V = r2 h , where r is radius and h is height.)

CHECK IT G3.5

A drainage pipe in the shape of a cylinder is 12 feet long and has a diameter of 10 feet. Approximately how much water is in this container if it is full?