Question

A ball has a diameter of 9 in. It consists of 2 parts. The inside is a spherical core with a diameter of 6 in. Surrounding the core is a layer of polyurethane.



What is the volume of the polyurethane?

Use 3.14 to approximate pi and express your answer in hundredths.

Answer 1

@Igreen

Answer 2

@iGreen

Answer 3

Volume of polyurethane = volume of the ball - volume of the inner core

Answer 4

@josephinevessey

Answer 5

I do not understand how you are suppose to solve it

Answer 6

these are both spheres whose volume is (4/3) pi r^3 where r = radius

Answer 7

for 9 we have to divide by 2 right since it is diameter

Answer 8

and change it into radius

Answer 9

use pi = 3.14 as in the question and the radius of each sphere = ha;lf the diameter

Answer 10

i dont know how to solve it srry

Answer 11

9 divided by 2

Answer 12

yes the radius of the whole ball = 4.5 and radius of inner core = 1/2 * 6 = 3

Answer 13

what do we do now?

Answer 14

plug those values into the formulas for the volume and work it out

volume = (4/3)*3.14*4.5^3 - (4/3)*3.14*3^3

Answer 15

use your calculator

Answer 16

first one I got 381.51

Answer 17

yes thats right - that is the volume of the whole ball

Answer 18

second one I got 113.04

Answer 19

what now?

Answer 20

well look at the formula - you subtract them

Answer 21

is the answer 268.47

Answer 22

= (4/3)*3.14*4.5^3 - (4/3)*3.14*3^3

Answer 23

yes

Answer 24

I have another question

Answer 25

plz post it seperately