Question

A 5/8 inch (inside) diameter garden hose is used to fill a round swimming pool 7.3m in diameter.How long will it take to fill the pool to a depth of 1.0m if water issues from the hose at a speed of 0.50m/s ?

Answer 1

V(pool) =π•D²•h/4
V= π•d²•vt/4
π•D²•h/4= π•d²•vvt/4
t=D²vh/d²•v

Answer 2

t = volume/(volume flow rate)
= (pi/4)*D^2*(depth)/ [(pi/4)*d^2*V]
= (D/d)^2*(depth)/V

d is the hose diameter. D is the pool diameter.
V is the water velocity leaving the hose.