A 100 litre open-topped tank is filled to the brim with salt water. The salt concentration in the water is 80 g/L. Fresh water then pours into the tank at the rate of 10 L/sec. Assume the fresh water mixes completely with the salt water. The excess water runs out over the top (also at the rate of 10 L/sec). 10 L/s (fresh water) 100 L
a) Find an equation that gives the amount of salt remaining in the tank after t seconds.
b) How much salt is left in the tank after one minute?
c) How much salt is left in the tank after 100 L of brine has flowed out over the top of the tank?
d) When will half of the salt in the tank have flowed out over the top of the tank?
e) When will the tank contain salt water at a concentration of 5 g/L?
