I need a formula to calculate the diameter of a spherical tank. When the volume is known in gallons?

Question

I am trying to work up a formula to figure out the volume of a spherical tank. When the volume is already known in gallons, and in this case, the volume is 105 gallons.

Answer 1

V(sphere) = 1/6*pi*d^3

so d = (6*V(sphere)/pi)^(1/3)

1 gal = 0.134 ft^3

so d  = (6*0.134/3.14)^(1/3) = 2.993 ft

Note: the previous answer multiplied by pi instead of dividing by pi