Question

Jenny has five exam scores of 69, 95, 75, 76, and 95 in her biology class. What score does she need on the final exam to have a mean grade of 8080? Round your answer to two decimal places, if necessary. (All exams have a maximum of 100 points.)

Answer 1

Given:

Five exam scores of Jenny 69, 95, 75, 76, and 95 in her biology class.

To find:

The score Jenny need on the final exam to have a mean of 8080

Solution:

Let marks obtained in the 6th exam be x

Mean= Sum of observation

          __________________

             No.of Observation

8080=(69+95+75+76+95)/6

8080 X 6=410 + x

x=48480-410

 =48070

But in the question, it has been given all exams have a marks of 100 points.

So,48070 can't be the answer.

Hence,I assume you've mistype the question,you've written 80 twice.

So,by taking mean 80 the answer will be =>

80=(410+x)/6

480-410=x

x=70

Therefore,she will have to score 70 marks in the last exam to get the desired average.