Answer :
Vol of water required to fill up the tub = 12-3 = 9
Rate of water per min = 3 -1.5 = 1.5/min
Using the formula vol = rt
t = v/r
t = 9/1.5 = 6
time taken = 6 mins
Rate of water per min = 3 -1.5 = 1.5/min
Using the formula vol = rt
t = v/r
t = 9/1.5 = 6
time taken = 6 mins