Distance between Moving Objects A Dodge Neon and a Mack truck leave an intersection at the same time. The Neon heads east at an average speed of 30 miles per hour, while the truck heads south at an average speed of 40 miles per hour. Find an expression for their distance apart d (in miles) at the end of t hours.

Math246 Lecture 5: Modeling with Differential Equations We will be looking at various applications of differential equations. Mixing Problem For these types of problems, we will be looking at the rate of change in the rate at which a liquid enters a tank. 1. A water tank that has a capacity of 2000 gallons initially has 400 gallons of water in it and 3 pounds of salt dissolved in it. Water enters the tank at a rate of 20 gallons per 1 (sin( ) +6) hour and the salt concentration is give2 by pounds per gallon. If the mixed solution exits the tank at a rate of 12 gallons per hour, how much salt is in the tank when it overflows So the concentration is equal to