Based on the diagram, Susan is using a visual representation of division to solve 1.4 divided by 0.2. Susan's reasoning is correct.
She has divided a rectangle with an area of 1.4 into 7 smaller rectangles with an area of 0.2 each. This shows that 1.4 divided by 0.2 is equal to 7.
Her reasoning is correct because she is using a valid mathematical operation (division) to solve the problem and the diagram accurately represents the division process.
Here is a more detailed explanation of her thinking:
Susan knows that the area of a rectangle is equal to its length times its width.
She also knows that division can be thought of as partitioning a whole into smaller equal parts.
In the diagram, the large rectangle represents the whole (1.4) and the smaller rectangles represent the equal parts (0.2).
Since the large rectangle is divided into 7 smaller rectangles, the answer to 1.4 divided by 0.2 is 7.
Therefore, Susan's reasoning is correct.