Solution: We know that:
Paul and Brett went to math class and were given the same expression to simplify. The expression they were given was 6 + 12 divided by 2(3) + 1.
Looking at the solution's by Paul and Brett, we clearly see that the Paul made a mistake at step 3.
6 + 12 ÷ 2(3) + 1
6 + 12 ÷ 6 + 1 Correct
18 ÷ 6 + 1 Incorrect It should have been 6 + 2 +1
According to order of operation's rule, division needs to done before addition.
Therefore, solution by Paul carries a mistake, while the solution by Brett is correct.