You know that the two water tanks the farmer has, drain at a rate of 2.5 gallons per minute.
You also know that Model S and ModelT hold 100 gallons of water each.
• Knowing the values given in the table for the tank Model S, you can find the its drainage rate as following:
Use the following formula:

Using the information given in the table, you can set up that:

Substituting values into the formula and evaluating, you get:

• Analyzing the graph given of Model T drainage rate, you can use the same formula:

In this case you know these points on the line:

Then you can set up that:

Substituting values and evaluating, you get:

Therefore, notice that:
- Model S Drainage rate is:

- Model T Drainage rate is:

The answer is: Model S and Model T drain faster than the existing tanks.