To get the weight of the aquarium we first calculate the volume of the aquarium.
Volume=(length*width*height)
V=30×14×18
V=7560 in³
But
weight of water is such that for every cubic inches, the weight is 0.036 lb
thus the weight of water will be:
0.036×7560=272.16 lb
Thus the total weight of the aquarium is:
272.16+22.5
=294.66 lb