SOLUTION: Tom has taken 5 of the 8 equally weighted tests in his US History class. He has an average score of 78.0 points. How many points does he need to earn on the 6th test to bring hi

Algebra ->  Algebra  -> Percentage-and-ratio-word-problems -> SOLUTION: Tom has taken 5 of the 8 equally weighted tests in his US History class. He has an average score of 78.0 points. How many points does he need to earn on the 6th test to bring hi      Log On

Ad: Algebra Solved!™: algebra software solves algebra homework problems with step-by-step help!
Ad: Algebrator™ solves your algebra problems and provides step-by-step explanations!

   

Question 440110: Tom has taken 5 of the 8 equally weighted tests in his US History class. He has an average score of 78.0 points. How many points does he need to earn on the 6th test to bring his average score to 80 points?
Answer by ewatrrr(10682) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi

 Tom has taken 5 of the 8 equally weighted tests in his US History class.  

He has an average score of 78.0 points.  Total point thru 5 tests = 5*78 = 390

How many points does he need to earn on the 6th test to bring his 

average score to 80 points?  Let x represent his points on his 6th test 

  (390 + x)/6 = 80

   390 + x = 480

         x =  90 points