
Elementary Math Fractions, Percentages, Word Problems, Equations, Inequations, Factorization, Expansion 
 LinkBack  Thread Tools  Display Modes 
May 11th, 2012, 03:29 AM  #1 
Newbie Joined: Jan 2011 Posts: 10 Thanks: 0  Percentages problem – need help adding percentages please
I need 40% overall to pass my exam. So far I have got: 55% of an exam worth 45% of overall grade, and 75% of an essay worth 10% of overall grade I have one more exam, worth 45% of the overall grade. What is the minimum percentage score I need to achieve to get an overall grade of 40%? I have no idea how to do the math, so any help is great. Thanks 
May 11th, 2012, 08:30 AM  #2 
Senior Member Joined: Jul 2010 From: St. Augustine, FL., U.S.A.'s oldest city Posts: 12,155 Thanks: 466 Math Focus: Calculus/ODEs  Re: Percentages problem – need help adding percentages pleas
Let x represent the minimal score you need. So we have: 0.45·0.55 + 0.10·0.75 + 0.45·x = 0.40 0.2475 + 0.075 + 0.45·x = 0.40 0.3225 + 0.45·x = 0.40 0.45·x = 0.0775 x = 0.17222... Hence, the minimal score is 17 2/9% 
May 11th, 2012, 08:33 AM  #3 
Newbie Joined: Jan 2011 Posts: 10 Thanks: 0  Re: Percentages problem – need help adding percentages pleas
Ah, you're great. Thanks a lot. I've always wondered how to do this. 
May 11th, 2012, 05:56 PM  #4  
Math Team Joined: Oct 2011 From: Ottawa Ontario, Canada Posts: 12,130 Thanks: 801  Re: Percentages problem – need help adding percentages pleas Quote:
 
May 25th, 2012, 01:56 PM  #5 
Math Team Joined: Sep 2007 Posts: 2,409 Thanks: 6  Re: Percentages problem – need help adding percentages pleas
You can just imagine a month old baby, lying in his crib, wondering how to do problems like this!


Tags 
adding, percentages, problem 
Search tags for this page 
Click on a term to search for related topics.

Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Interesting problem on percentages.  sf7  Elementary Math  2  March 22nd, 2014 07:17 AM 
Adding disproportionate percentages  NAL Grunt  Elementary Math  1  December 2nd, 2011 02:25 PM 
Percentages  cafegurl  Elementary Math  1  January 26th, 2010 01:45 PM 
Percentages:  cafegurl  Elementary Math  6  July 26th, 2009 10:20 PM 
More on Percentages.  jloffredo  Elementary Math  2  January 13th, 2009 06:58 PM 