<PRE><B>Question 667939</B>
I have an 82 average in Math, and
 I just got a 78% on a quiz. 
If quizzes are 35% of my grade, what is my new average?
:
Then the average must by 65% of the grade
35/100 = 7/20
65/100 = 13/20
:
Using the ratio 13:7 and assume 20 grades
:
{{{(13(82) + 7(78))/20}}} = 80.6% is the new average

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