Use the image below to answer the two-part question.
A grid with 10 equal columns is shown with 5 columns shaded in. A second grid is shown, identical in size, containing 100 squares with 3 squares shaded in.
Part A
Write a problem that represents the addition model shown above. Don't solve the problem.
Part A:
If you add the number of shaded squares in the first grid to the number of shaded squares in the second grid, how many squares in total are shaded?
Emma incorrectly gave the sum as 8/100. Explain Emma's mistake and use the model to correct her work. Solve the problem in your answer.
(2 points)
Emma's mistake was that she added the total number of shaded squares in each grid separately, instead of adding the shaded squares together.
To correct Emma's mistake, we need to add the number of shaded squares in the first grid to the number of shaded squares in the second grid. In the first grid, there are 5 shaded squares, and in the second grid, there are 3 shaded squares. Adding these together, we get:
5 + 3 = 8
Therefore, the correct answer is that there are 8 squares shaded in total, not 8/100 as Emma incorrectly stated.