Question

A. A student has grades of 65,80,78, and 92 on four tests. Use s to represent the student's grade on the next test. Write an expression for the average of the five tests.
B. The student wants to have an average of 80 after the fifth test. Use the expression you wrote in part a to write and equation.
C. Solve the equation to find the grade the students must earn on the fifth test to have an average of 80 for the class.

Answer 1

a?

Answer 2

@keegq

Answer 3

Part A

Answer 4

Since 's' denotes the next test we can rewrite the series as 65,80,78,92,s
So now we just use the regular mean average formula: get the sum of all and divide by how many there are. Think you have it now?

Answer 5

yes thanks