Question

Kara has five exam scores of 89, 82, 69, 79, and 70 in her biology class. What score does she need on the final exam to have a mean grade of 80? Round your answer to two decimal places, if necessary. (All exams have a maximum of 100 points.

Answer 1

91

Explanation:

`(89+82+69+79+70+x)/(6)` = 80 Combine like terms

`(389+ x)/(6)` = 80 Multiple by sides by 6

380 + x = 480 Subtract 389 from both sides.

x = 91