SOLUTION: Scott showed improvement on his five math exams throughout the semester improving by 3% on each successive exam. If the fifth exam (final exam) counted twice as much as the first f

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Question 1048350: Scott showed improvement on his five math exams throughout the semester improving by 3% on each successive exam. If the fifth exam (final exam) counted twice as much as the first four exams and his average was 79% for all five exams, what score did he receive on his first exam?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
a%5Bn%5D+=+a%5B1%5D%2Ar%5E%28n-1%29
sum%28+a%5Bi%5D%2C+i=1%2C+4+%29+=+a%5B1%5D%28%281-.03%5En%29%2F%281-r%29%29
sum%28+x%2C+i=1%2C+4+%29+=+x%28%281-.03%5E4%29%2F%28.97%29%29 sum of first 4
%28%28x%281-.03%5E4%29%2F%28.97%29%29+%2B+2x%28%281-.03%5E4%29%2F%28.97%29%29+%29%2F+5+=+79+
3x%28%281-.03%5E4%29%2F%28.97%29%29+=+395
x = 395%2A.97%2F%283%281-.03%5E4%29%29 use Your Calculator