
a)r-5 h-20
V=π x r x r x h
V=3.14 x 5 x 5 x 20
V=1570 cm3
b)r-.5 h-1
V= π x r x r x h
V=3.14 x .5 x .5 x 1
V=0.785 m3
c)r-9 h-7.5
V= π x r x r x h
V=3.14 x 9 x 9 x 7.5
V=1907.55 cm3
r-.25 h-20
V=π x r x r x h
V=3.14 x .25 x .25 x 20
V=3.925 cm3
This is a place for the community of learners in Room 8-41 to learn and enjoy math. It is an extension of the classroom making it accessible 24 hours a day, 7 days a week.







Length Width Height Volume
a)7cm 2cm 5cm 70cm3
lb)12cm 9cm 10cm 1080cm3
c)16cm 15cm 5cm 1200cm3
You can easily fill in this chart by simply asking yourself what multiplied by what equals the volume or creating an algebraic equation for each one. For example: a) 7x2=14, so 14xa=70m3, you replace the variable (a) with the number that best suits that equation which is 5. So thats how I figured out question 11.
16. Cindy’s aquarium stands 75 cm tall and
has a base that measures 1.2 m × 80 cm.
At one point during the initial fi lling, the
aquarium has a 12-cm depth of water in
it. Cindy needs to fi ll it to 15 cm from the
top before she adds the fi sh. Draw a
diagram and label the dimensions of the
aquarium. Determine how much more
water Cindy must add before she puts in
the fi sh.
Red=Math information
Scince you need a 15cm gap from the top you need to subtract 12 from 75 which is 63 and then you subtract 15 from 63 and you get 48. Now we have to find the volume of water we need to use in the tank.
V=lxwxh
v=120cmx80cmxh
v=9600cm2x48cm
v=460 800 cm3.
So Cindy needs to add 460 800cm3 of water before she adds the fish.
17.
A contractor is excavating a rectangular
hole 10 m × 12 m × 3 m to pour the
foundation for a house. A dump truck
with a capacity of 9 m3 is used to haul
away the excavated soil. How many trips
does the truck need to make?
Find volume of rectangular hole:
V=lxwxh
v=10mx12mxh
v=120m2x3m
v=360m3
360m3/9m3=40m3
So the truck driver will have to make 40 trips.
Cylinder Volume and Volume Problems
Cylinder Problem

d=r/2
d=20cm/2
d=10cm

Volume of Cube:
Side x Side x Side= Area of cube
7 cm x 7 cm x 7 cm = 343 cm³

(3.14 x 12cm x 12cm) x 15cm= v
452.16cm² x 15cm=6782.4cm³
6782.4cm³ / 4= 1695.6cm³
Volume= 1695.6cm³

Outer Volume:
d/2= r
10cm/2= 5cm
( π x r x r) x h= v
(3.14 x 5cm x 5cm) x 40cm= v
78.5cm² x 40cm= 3140cm³
Volume of Outer Pipe= 3140cm³
Inner Volume:
d/2= r
8cm/2= 4cm
(π x r x r) x h= v
(3.14 x 4cm x 4cm) x 40cm= v
50.24cm² x 40cm= 2009.6cm³
Volume of Inner Pipe= 2009.6cm³
Subtraction of Both Pipes:
Formula outer pipe - inner pipe= capacity of pipe
3140cm³ - 2009.6cm³= 1130.4cm³
Capacity of Pipe= 1130.4cm³
EXTRA
Here is a link of a volume of a cylinder calculator.









