Answer :
Lets denote the hoses as variables.
small hose per unit time = h
larger hose per unit time = H
h = 1/2H
40(h+H) = full
40(h+2h) = full
40(3h) = full
120(h) = full
120 minutes or 2 hours
small hose per unit time = h
larger hose per unit time = H
h = 1/2H
40(h+H) = full
40(h+2h) = full
40(3h) = full
120(h) = full
120 minutes or 2 hours