3. 60 divide by 360 times pi times (8)2=33.51 squared inch
4. 120divide by 360 times pi times (5 over 2)2=40.9 squared inch
The answer is 1,695.6 in³.
The volume of the empty space is the difference of the bigger cylinder and the smaller cylinder: V = V1 - V2
The volume of the bigger cylinder is:
V1 = π r² h
r = 10 in
h = 15 in
π = 3.14
V1 = 3.14 * 10² * 15 = 4,710 in³
The volume of the smaller cylinder is:
V2 = π r² h
r = 8 in
h = 15 in
π = 3.14
V2 = 3.14 * 8² * 15 = 3,014.4 in³
The volume of the empty space is:
V = V1 - V2 = 4,710 in³ - 3,014.4 in³ = 1,695.6 in³
The answer is 25%
(1)
If 64 is 100%, 48 is how much percent:
64 : 100% = 48 : x
x = 100% * 48 : 64
x = 75
(2)
Percent of decrease is:
100% - x = 100% - 75% = 25%
