A volcanic plug shaped like a cone has a diameter of 24 km and a height of 3 km.



What is the volume of the plug?

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


and

Ellie’s bird feeder is shaped like a cone with a height of 24 in. and a radius of 3 in. Packages of bird seed are cylindrical and come in different sizes.



What is the height of the package that has a radius of 6 in. and contains exactly enough bird seed to fill the feeder?

Use 3.14 to approximate pi.


Sagot :

volume of a cone=height times 1/3 times are of base
area of base=circle=pi times radius^2
pi is aprox in this problem 3.14
volume=height times 1/3 times 3.14 times radius^2
height=3
diameter=2radius
radius=1/2diameter
radius=1/2 times 24=12

volume=3 times 1/3 times 3.14 times 12^2
volume=1 times 3.14 times 144
volume=452.16 km^3 cubic km


second:
so bird feeder height=24
radius=3
volume=24 times 1/3 times 3.14 times 3^2
volume=8 times 3.14 times 9
volume=226.08
then find height of package with same volume
226.08=height times 1/3 times 3.14 times 6^2
226.08=height times 3.14 times 36 times 1/3
226.08=height times 3.14 times 12
226.08=heigh times 37.68
divide both sides by 37.68
6=height

the height is 6 inches




ANSWERS
1.    452.16 km^3 or 452.16 cubic km

2.    6 inches or 6 in