<PRE><B>Question 783239</B>
A friend has a 79% average before the final exam for a course.
 That score includes everything but the final, which counts for 20% of the course grade.
From the information given, we know that the ratio of Grades to Exam is 4:1
:
What is the best course grade your friend can earn? %
Assume the exam grade is 100
Av = {{{(4(79) + 100)/5}}}
Av = {{{416/5}}}
Av = 84% best grade
: 
What is the minimum score would your friend would need on the final to earn a 75% for the course? %
{{{(4(79)+E)/5}}} = 75
Multiply both sides by 5
316 + E = 375
E = 375 - 316
E = 59% on the Exam would give an average of 75%</PRE>