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Madihakazi
Nov 30, 2010, 09:21 AM
A solid metal sphere has a radius of 9 cm.

a. Calculate the volume in cm cube of the sphere.

The sphere is melted down and the resulting metal is used to make 20 identical right circular cylinders each with height 15 cm.
b. Calculate the radius, in cm, of each cylinder.

c. Write down in standard form, the radius in metres of each cylinder.

Unknown008
Nov 30, 2010, 10:45 AM
a) The volume of a sphere is given by:

V = \frac43 \pi r^3

b) Find the volume of each cylinder first.
Then using:

V = \pi r^2h

find the value of r, knowing V and h.

c) Can you do this? Numbers in standard form are written as a number between 0 and 10 exclusive multiplied by 10 raised to the appropriate power.

Madihakazi
Nov 30, 2010, 11:31 PM
Thanks sir... I sort of knew this answer from the start but was just trying to confirm... u r a really great teacher