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### ratnaveera says

If you need to find out the height and radius of a cylindrical tank with the capacity of 500 liters, you can get them as follows

Volume of any cylindrical tank = 3.14*r*r*h

Say the height is thrice the radius of the tank and now the formula can be written as

3.14*r*r*3*r

= 3.14*3*r^3

=500000 cc

r^3 = 500000/(3.14*3)

r^3 = 53078.55

r = 37.58

Now the radius of the tank that holds 500 liters is 37.58 cm and height is 112.74 cm

### academysigma says

Because there are two variables r and h, there's going to be infinite combinations of r and h which will yield V = 500000.

But you can solve either for 'r' or 'h' algebraically.

Firstly note that 500 litres = 500000 cm³ = V

I chose to solve for 'h' here

(so the dependent variable is h, and independent variable is r)

h = 500000 / ( Pi * r² )

Then choose any positive value of r, say

r = 100, then h = 500000 / ( Pi * 100² )

= 15.9155 cm

You can plot a graph to show the combinations of r and h which yields V = 500000