Finding the volume of aquariums

I am doing a geometry assignment, but I don't understand a question.For example, it says, "imagine that your business designs and builds custom aquariums. In order to make sure that a particular aquarium fits certain specifications, you have to adjust some of the dimensions to make sure that you maintain the volume of a tank. Volume= length•width•height. You also know that 231 cubic inches are equal to a gallon. Use this information to solve each problem below." And the questions says, " You think it would be a great idea to market a 22-gallon aquarium that is a perfect cube. Estimate the dimensions and then check your guess to see how close you can get. What operation do you need to know to get an exact answer (to the nearest tenth of an inch)?" I have no idea how to do this question so anything helps. Thank you.

right a gallon is a unit of volume.

We want 22 of them, therefore we want to multiply 231 by 22 to get our volume in cubic inches.

so V = 5082 cubic inches.

We also know that the aquarium is to be a perfect cube. Therefore the length is equal to the width as is the height.

Therefore our equation for Volume becomes V = L^3

So if we take the cube root of the Volume we will get our answer

L = 17.2 inches.

22 gallons is 22 * 231 cubic inches or 5082.

For a perfect cube we need the length, width & height to be the same.

We can express this as x^3 = 5082.

Guessing answers for x:

10 gives a volume of 1000 (too small)
20 gives a volume of 8000 (too big)
16 gives 4096 (too small)
17 gives 4913 (really close)
18 gives 5832 (further away)
17.1 gives 5000.2
17.2 gives 5088.4 so this is the closest answer to 0.1 of an inch

An exact answer would need a cube root function