Answer:
I think maybe E. I never really solved a question like this before but to find the mean you add up all the numbers, then divide by how many numbers there are. In other words it is the sum divided by the count.
Step-by-step explanation:
There is no error on Jill's part. The teachers error was that she marked it wrong.
2481.7
^ is the tenth place.
The 5 would either round it up or down by one-tenth. Since we like big numbers... we'll round it to 7 from 6.