Susan has grades of 84, 65, and 76 on three math tests. what grade must he obtain on the next test to have an average of exactly 80 for the four tests?
Average of 4 tests = 80 Total of the 4 tests = 80 x 4 = 320
Total of the 3 grades = 84 + 65 + 76 = 225
Grades needed for the 4th test = 320 - 225 = 95
------------------------------------------------------------- Answer: She needs to score 95 for the next test. -------------------------------------------------------------
