Question 1058965
86, 78, 68, 92, 72 are two-thirds of the course grade and some unknown T is worth one third of the course grade.  Based on each normal test is 100 percentage points,   {{{5*100=500}}} is {{{2/3}}} of the course and T is {{{1/3}}} of the course.  Trying to think as practically as you can,  half of the 500 percentage points is 250 percentage points, which is  ONE THIRD of the course grade.  Total percentage points for the course is  {{{500+250=750}}}.


Reread a few times if needed until you understand that.


Theresa needs average 80 to 90 percent for grade of B.  What should score T be?



{{{80<(86+78+68+92+72+T)/750<90}}}