Answer: Justin should have multiplied 3.8 and 7.9 first.
Explanation:
The equation that was given with regards to the question is 12.5 + 7.9x and we are told that the value of x = 3.8
The error made by Justin was that he didn't multiply 3.8 and 7.9 at first. Solving the equation will be:
= 12.5 + 7.9x = 12.5 + 7.9(3.8)
= 12.5 + 30.02
= 42.52