Answer:
158.4 pounds
Step-by-step explanation:
first find the volume of the tank
[tex]V = 30 \times 30 \times 80[/tex]
[tex]V = 72000 cm^3[/tex]
to convert this to m^3 we know that 1m = 100cm
[tex]V = 72000 cm^3 \times \left(\dfrac{1\,\text{m}}{100\,\text{cm}}\right)^3[/tex]
[tex]V = 72000 cm^3 \times \left(\dfrac{1\,\text{m}^3}{100^3\,\text{cm}^3}\right)[/tex]
the cm^3 cancel out.
[tex]V = \dfrac{72000}{100^3} m^3[/tex]
[tex]V = 0.072\,m^3[/tex]
by simply converting the side-lengths to meters beforehand can give you this answer directly:
[tex]V = 0.3 \times 0.3 \times 0.8 = 0.072 m^3[/tex]
it is given that 1 meter cube of water weighs about 2200 pounds.
[tex]1\,m^3 = 2200 \,\text{lb}[/tex]
multiply both sides with 0.072 to find our answer:
[tex]1\,m^3 \times 0.072 = 2200 \times 0.072 \,\text{lb}[/tex]
[tex]0.072\,m^3 = 158.4 \,\text{lb}[/tex]
hence the weight of the water in the tank would be 158.4 pounds!
