In 1. He did not use the correct of making it an additive inverse. Usually to make additive inverse, one has to add the same numbers but opposite signs with it to result for a zero.
So the answer for step 1. would be... - 8.3 + 8.3 + 9.2 - 9.2 - 4.4 + 4.4 + 3.7 - 3.7
In 2. he also had errors because commutative property states that we can place the numbers in a different format but the result number will always be the same.
So the original problem is −8.3 + 9.2 − 4.4 + 3.7 which results 0.2 but in Allen's workout: −8.3 + 4.4 + 9.2 + 3.7 results 9
Actually the answer is B. cuz A is incorrect because he made errors. D is also incorrect because changing the grouping of numbers are commutative property. And step 2 is actually commutative so its not incorrect.
