Andrew is showing his work in simplifying - 4.5 + 4.2 + 5.6 - 7.3. Identify any errors in his work or in his reasoning. Write feedback to Andrew explaining the mistake he made and how to correct his work.

Step Work Reasoning

-4.5 + 4.2 + 5.6 - 7.3 Original problem

1 - 4.5 + 4.2 + 5.6 + (-7.3) Additive inverse

2 - 4.5 + (-7.3) + 4.2 + 5.6 Commutative property

3 (-4.5 + (-7.3)) + (4.2 + 5.6) Associative property

4 - 11.8 + 9.8 Simplify

5 - 21.6 Simplify

Question

Mathematics

Kianna Bolton

23 August, 15:35

Andrew is showing his work in simplifying - 4.5 + 4.2 + 5.6 - 7.3. Identify any errors in his work or in his reasoning. Write feedback to Andrew explaining the mistake he made and how to correct his work.

Step Work Reasoning

-4.5 + 4.2 + 5.6 - 7.3 Original problem

1 - 4.5 + 4.2 + 5.6 + (-7.3) Additive inverse

2 - 4.5 + (-7.3) + 4.2 + 5.6 Commutative property

3 (-4.5 + (-7.3)) + (4.2 + 5.6) Associative property

4 - 11.8 + 9.8 Simplify

5 - 21.6 Simplify

+2

Answers (1)

Know the Answer?

Valerie Soto · Answer 1

The issue is from line 4 to line 5.

Andrew added the numbers together as if it is:

- (11.8 + 9.8)

That way is incorrect.

The correct way for Andrew to visualize the equation is to rearrange it to become:

9.8 - 11.8

To get 2 as the answer