SOLUTION: In a math class at the community college, only five chapter exams are given and an 80% must be achieved in order to take the state exit exam. Pam has completed the first four exams

Algebra ->  Customizable Word Problem Solvers  -> Misc -> SOLUTION: In a math class at the community college, only five chapter exams are given and an 80% must be achieved in order to take the state exit exam. Pam has completed the first four exams      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 513083: In a math class at the community college, only five chapter exams are given and an 80% must be achieved in order to take the state exit exam. Pam has completed the first four exams with scored of 71,84,79, and 81. Find the minimal score Pam can make on the fifth exam in order to take the state exit exam?
Answer by umail08(87) About Me  (Show Source):
You can put this solution on YOUR website!
To find the average you would add your test grades together and divide by the number of tests.
In this problem I am translating 80% to mean an average of 80.
Therefore:
(71+84+79+81+x)/5 = 80 … the variable ‘x’ represents the score for the fifth exam
(315+x)/5 = 80 … simplified parenthesis and changed percentage to a decimal
315+x = 5(80) … multiply both sides by the denominator 5.
315+x=400
315-315+x=400-315
x=85 is the grade needed to end up with an 80 average.