3. During his stay at a hotel, a man decides to take a warm bath. He fills the tub with 200 liters of water and adds200 grams of liquid soap

to the tub. The man mistakenly leaves the tap open, which keeps pouring water at arate of 1 liter/hour. Find the amount of soap y(t) left in the tub after time t. Hint: use liters, grams and hoursas units of measure, so you can just omit them and focus on the math problem! E.g., the initial amount of soapwill be 200 rather than 200g.

Fig: 1

Fig: 2