 |
US $8.99
Volume Maths help! with steps?
1. The local council has issued rectangular
green ‘Big Bins’ to all ratepayers. Each
of these is 95 cm high, 55 cm wide and
65 cm deep. These will be emptied once
a week into a truck which carries a
cylindrical hopper that is 6 m long and
has a diameter of 4 m. How many full
bins will be needed to fill the truck?
(Answer to the nearest bin.)
2.A 3.5 m long plastic pipe is to be used
for drainage. If it has an outer radius of
12 cm and an inner radius of 9 cm, find
the volume of plastic needed to construct
it. Express your answer in m3 correct to
two decimal places.
1)
1 m =100cm
bin is 0.95 x 0.55 x 0.65 = 0.34m cu.
cylinder volume=pi x (dia/2)^2 x length
=22/7 x 4 x 6
75.43 m cu.
Bins to fill=75.43 / 0.34
=221.85
221 full bins to fill up the truck
2)
volume with outer radius
=pi x 0.12^2 x 3.5
=3.14 x 0.0144 x 3.5
=0.16 m cu.
Volume with inner radius
=pi x 0.09^2 x 3.5
=3.14 x 0.0081 x 3.5
=0.09
Volume of plastic needed
=volume with outer radius - Volume with inner radius
=0.16 - 0.09
=0.07 m cu
Take note that 1 m cu is 1m x 1m x 1m, so 1m cu is not equivalent to 100cm cu but 100cm x 100cm x 100cm, or 1000000cm cu.