<PRE><B>Question 5064</B>
Average his four grades together by adding and dividing by 4:
{{{ (86 +80 + 84 + 90) /4) = 85}}}


Let x = grade on the final, which counts as two grades, whereas his average on the other tests, which is 85, counts as a single grade.


Solve the following equations:


For a B in the class:  
{{{ (85 + x + x ) / 3 = 80}}}
Multiply both sides by 3:
85 + 2x = 240
2x = 155
x= 77.5


For an A in the class:  
{{{ (85 + x + x ) / 3 = 90}}}
Multiply both sides by 3:
85 + 2x = 270
2x = 185
x= 92.5


R^2 at SCC

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