**Answer:**

The actual number of calories that Mya burned when she

trained for 30 minutes is 240.

**Step-by-step explanation:**

We have an exponential function that is the best fit for the number of calories Mya burns, in function of time (minutes).

The function is:

Where y: calories burned, and x: training time.

Whenever we use regression models, we have a real value and a predicted value. The difference between them, the measure we want to minimize when we adjust with this typo of models, is called **residual**.

In the table is shown as one of the columns.

For example, for x=10 minutes, we have a real value of 30 and a predicted value of 78.36, so the residual becomes e=30-78.36=-48.36.

For x=30 minutes, we have only the residual, that has a value of 5.53. That means that the predicted value, which we can calculate, is 5.53 below the real value.

The predicted value for x=30 is:

Using the equation for the residual e, we can calcualte the actual number of calories that Mya burned in 30 minutes: