Answer:
both Jenna and Mia got the same answer because the answer they got is correct but they used their own techniques to reach for the answer.
Mia's steps are time efficient enough by shortening the length of the sum and jumping steps...
Jenna is also correct in her own way, she wrote the full steps and explanation of the answer stepwise which is time consuming but cannot be wrong at the end throughout the steps. Even if she gets wrong she can quickly find the place of the mistake.