Question

To pass algebra II requires an average of at least 70 on four tests. A student has scores of 80, 62, and 73. What possible scores on the fourth test would guarantee this student a passing score in the class?

Answer 1

Answer: Let x be the student's score on the fourth test. The average of the four scores must be at least 70, so we can write the equation:

(80 + 62 + 73 + x) / 4 >= 70

Expanding and simplifying the left-hand side:

(215 + x) / 4 >= 70

Multiplying both sides by 4 to isolate x:

215 + x >= 280

Subtracting 215 from both sides:

x >= 65

So, the student must score at least 65 on the fourth test in order to guarantee a passing average of 70. Any score higher than 65 will also guarantee a passing average.

Explanation: