Question

Use the hundredth grids below to answer the questions. The first two hundredth grids show Sophia's work. The second two hundredth grids show Aiden's work. Part A Which student correctly models the problem 1.25 + 0.4. Type your answer in the box. Part B What is the correct answer for 1.25 + 0.4? Part C Explain the errors made by the incorrect student. Refer back to the models and use equations to support your explanation.

Answer 1

Grids are used to represent numbers in their place value.

The result of $\mathbf{1.25 + 0.4}$ is 1.65

The expression is given as: $\mathbf{1.25 + 0.4}$

Express the numbers as fractions

$\mathbf{1.25 + 0.4 = \frac{125}{100} + \frac{4}{10}}$

Split

$\mathbf{1.25 + 0.4 = 1 + \frac{25}{100} + \frac{4}{10}}$

Rewrite to model a 10 by 10 grid:

$\mathbf{1.25 + 0.4 = \frac{100}{100} + \frac{25}{100} + \frac{40}{100}}$

The above means that:

• 100/100: A whole 10-by-10 grade is shaded
• 25/100: 2 columns and 5 squares are shaded on the third column.

Because there are 5 unshaded squares, 40/100 will be split to 5/100 + 35/100

So, the remaining 5 squares will be shaded.

Then, 3 columns and 5 squares are shaded

Base on the above highlights, Sophia is correct.

The result of the computation is as follows:

$\mathbf{1.25 + 0.4 = \frac{100}{100} + \frac{25}{100} + \frac{40}{100}}$

$\mathbf{1.25 + 0.4 = \frac{100+25+40}{100} }$

$\mathbf{1.25 + 0.4 = \frac{165}{100} }$

$\mathbf{1.25 + 0.4 = 1.65}$

Hence, the result is 1.65

Read more about hundredth grids at:

https://brainly.com/question