SOLUTION: the average of 10 test is 82. when the highest score is dropped, the average of the remaining scores is 80. what was the score that was dropped?

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Question 546949: the average of 10 test is 82. when the highest score is dropped, the average of the remaining scores is 80. what was the score that was dropped?
Answer by mathie123(224) About Me  (Show Source):
You can put this solution on YOUR website!
Let x_1 be the score of the lowest test, x_2 be the score of the second lowest test, and so forth until x_10 is the score of the highest test.
We have:
%28x_1%2Bx_2%2Bx_3%2Bx_4%2Bx_5%2Bx_6%2Bx_7%2Bx_8%2Bx_9%2Bx_10%29%2F10=82
x_1%2Bx_2%2Bx_3%2Bx_4%2Bx_5%2Bx_6%2Bx_7%2Bx_8%2Bx_9%2Bx_10=820 (1)
We also know that
%28x_1%2Bx_2%2Bx_3%2Bx_4%2Bx_5%2Bx_6%2Bx_7%2Bx_8%2Bx_9%29%2F9=80
x_1%2Bx_2%2Bx_3%2Bx_4%2Bx_5%2Bx_6%2Bx_7%2Bx_8%2Bx_9=720 (2)
Equations (1)-(2) leaves:

x_10=100

Therefore, the highest score is 100%.